It looks like we no longer need these lintian overrides:
- `package-contains-documentation-outside-usr-share-doc` got resolved
by excluding these directories from our source package
- the other one was a false positive that looks like it got fixed in
Debian
Also improve upload script to force push changelog branches.
Lintian v2.115 (which is run on Debian servers) still produces
pedantic warnings, but there seems to be a bug - no matter what
pattern I add to `lintian-overrides`, I can't get it to ignore
the files. The following version v2.116 has these rules built in,
so we don't need `lintian-overrides` anymore.
(cherry picked from commit 134e084b80)