lintian.tags: remove license-problem-gfdl-invariants

It was reported to have false positives when the "no invariant
sections" notice has markup.

config/debian/lintian.tags

@@ -22,7 +22,6 @@ lintian:
     - install-info-used-in-maintainer-script
     - invalid-date-in-debian-changelog
     - latest-debian-changelog-entry-reuses-existing-version
-    - license-problem-gfdl-invariants
     - license-problem-json-evil
     - license-problem-non-free-RFC
     - license-problem-nvidia-intellectual