v1.9.6: update version numbers

v1.9.5: update version numbers

v1.8.6: update version numbers

Merge pull request #7270 from libgit2/copilot/backport-v19-4

backports for v1.9.4

Final final v1.9.3 updates (#7250)

ci: use newer artifact action

Another CI update for artifact action version.

v1.9.2: update changelog and version numbers

Merge pull request #7084 from libgit2/ethomson/v1.9.1

Merge pull request #6990 from libgit2/ethomson/ci

Merge pull request #6936 from libgit2/ethomson/v1.8.4

libgit2 v1.8.4