The interface changed in incompatible ways between Debian 10 (buster)
and Debian bullseye.

There are incompatible changes in some Python modules that make the
tests fail. As it is a new test, allow the failure until this is
fixed.

Some Python 2 modules no longer exist in Debian bullseye, so trying to
satisfy all build-dependencies in d/control would fail there.  For now
just install them in `run-ci` where we can modify the list of package
to install dynamically.

This way we can also run Python 3 tests in parallel without requiring
more resources in total.

Otherwise if one accepts multiple uploads in `dak process-new`, but
only edits the `COMMENTS` file for one `.changes` file one would end
up accepting an upload into a public suite.  This would be a problem
for uploads fixing embargoed issues.

4800f574 was a bit too enthusiastic
with removing executable bits.

This prevents encoding errors with python2.

It is no longer executable.

These are displayed during new processing.

The subprocess module has been unused since 400066ea
(daklib/rm.py: format date in python).

Fixes:

    daklib/architecture.py:113: SyntaxWarning: "is" with a literal. Did you mean "=="?

with Python >= 3.8.

It looks like some removal records had trailing whitespace which
confuses users of the deb822 file.

Reference: https://bugs.debian.org/960504

This reverts commit e43911e2.

* pr-200:
  dak rm: allow removal of binaries without source

* pr-199: (44 commits)
  Always run python3 tests, they succeed now.
  ci: remove stretch tests
  test 2001-cruft: add cruft report
  test 2000-dinstall: run make-changelog
  Add test 0006-dm-commands
  Testsuite fixtures: change some uploaders and add extra package
  tests: 2003-c-s-propup: remove first dinstall call
  test 0005-encoding: add extra checks
  integration-tests: add check_output function
  run-ci: don't run 2to3, it's not needed anymore
  run-ci: add annotated coverage report
  gitlab-ci: coverage job only uses py2 data
  integration-tests/dak-coverage.sh: fix coverage when working dir changes
  integration-tests/common: add function to save ci artifacts
  run-ci: define DAK_CI_OUTPUT_DIR
  daklib/dbconn.py: use textutils.force_to_utf8 for contents filename
  daklib/utils.py: handle encoding in gpg_get_key_addresses using six
  daklib/checks.py: use six function in check_fields_for_valid_utf8
  daklib/dbconn.py: set database connection to utf-8 for python3
  load_keys: make sure data from gpg is str
  ...

* utf8-filenames:
  For FTP auto rejection of non UTF-8 filenames, add a renamed Lintian tag but retain the old one.