* Create and validate standardized java source header

Update Checkstyle to validate all java source files have a standard
header. Remove FixLiscenseHeaders.java unit test as it duplicates
Checkstyle functionality. Standard header is block java comment, instead
of dangling Javadoc comment. Create standard header template
(HEADER_JAVA) in project root. Reference header template in
build.gradle. Update CONTRIBUTING.md to exact text of header template.

* Convert Licenses from dangling Javadoc to block comment

Standardize License based off of HEADER_JAVA file. All headers are block
Java comments.

* Restoring FixLicenseHeaders.java and updating CONTRIBUTING date

* Updated License dates to 2016

Several files had 2017 dates for License. Checkstyle now specifically
looks for 2016 date in License comments.

* Fix bad logic for header check in FixLicenseHeaders test

Bumps build-info-extractor-gradle from 4.20.0 to 4.21.0.
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

* #7195 Allow zip result to be garbage collected

* Also `null` collected values on error and complete

* Update MaybeZipArray.java

* Update SingleZipArray.java

* Update MaybeZipArray.java

* Update SingleZipArray.java

* Update MaybeZipArray.java

* Update MaybeZipArray.java
Co-authored-by: NAlex <alex@xenonlightz.de>
Co-authored-by: NDavid Karnok <akarnokd@gmail.com>

Bumps [mockito-core](https://github.com/mockito/mockito) from 3.7.7 to 3.8.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](https://github.com/mockito/mockito/compare/v3.7.7...v3.8.0)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps [biz.aQute.bnd.gradle](https://github.com/bndtools/bnd) from 5.2.0 to 5.3.0.
- [Release notes](https://github.com/bndtools/bnd/releases)
- [Changelog](https://github.com/bndtools/bnd/blob/master/docs/ADDING_RELEASE_DOCS.md)
- [Commits](https://github.com/bndtools/bnd/commits)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps gradle-animalsniffer-plugin from 1.5.2 to 1.5.3.
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps jmh-gradle-plugin from 0.5.2 to 0.5.3.
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps [junit](https://github.com/junit-team/junit4) from 4.13.1 to 4.13.2.
- [Release notes](https://github.com/junit-team/junit4/releases)
- [Changelog](https://github.com/junit-team/junit4/blob/main/doc/ReleaseNotes4.13.1.md)
- [Commits](https://github.com/junit-team/junit4/compare/r4.13.1...r4.13.2)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps [gradle-maven-publish-plugin](https://github.com/vanniktech/gradle-maven-publish-plugin) from 0.14.1 to 0.14.2.
- [Release notes](https://github.com/vanniktech/gradle-maven-publish-plugin/releases)
- [Changelog](https://github.com/vanniktech/gradle-maven-publish-plugin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/vanniktech/gradle-maven-publish-plugin/compare/0.14.1...0.14.2)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps [gradle-maven-publish-plugin](https://github.com/vanniktech/gradle-maven-publish-plugin) from 0.13.0 to 0.14.1.
- [Release notes](https://github.com/vanniktech/gradle-maven-publish-plugin/releases)
- [Changelog](https://github.com/vanniktech/gradle-maven-publish-plugin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/vanniktech/gradle-maven-publish-plugin/compare/0.13.0...0.14.1)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

* 3.x: Release to Sonatype directly

* Update build.gradle

* Update gradle.properties

* Turn RS into compile dependency in POM

* Fix the POM of the snapshot/artifactory upload

Co-authored-by: NWayne_Yang <wayne_yang@perfectcorp.com>

Bumps build-info-extractor-gradle from 4.19.0 to 4.20.0.
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Issue-Id: #7154
Co-authored-by: NSergej Isbrecht <sergej.isbrecht@gmail.com>

* Support for scheduled release of threads in Io Scheduler

* Test for rx3.io-scheduled-release

* Fix tests, addressed Javadoc feedback

Bumps build-info-extractor-gradle from 4.18.3 to 4.19.0.
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

* 3.x: onReduceBackpressure internals cleanup

* Update FlowableOnBackpressureReduceTest.java

* Update FlowableOnBackpressureReduceWithTest.java

Bumps [mockito-core](https://github.com/mockito/mockito) from 3.7.0 to 3.7.7.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](https://github.com/mockito/mockito/compare/v3.7.0...v3.7.7)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

* 3.x: Update marbles of amb(), ambArray() and ambWith()

* Fix image size

Bumps [mockito-core](https://github.com/mockito/mockito) from 3.6.28 to 3.7.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](https://github.com/mockito/mockito/compare/v3.6.28...v3.7.0)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps build-info-extractor-gradle from 4.18.2 to 4.18.3.
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Bumps [guava](https://github.com/google/guava) from 30.0-jre to 30.1-jre.
- [Release notes](https://github.com/google/guava/releases)
- [Commits](https://github.com/google/guava/commits)
Signed-off-by: Ndependabot-preview[bot] <support@dependabot.com>
Co-authored-by: Ndependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

* fix javadoc url from 2.x to 3.x

* using suggested fix by reviewer