Update libgit2 to v1.8.4 (#162)

* Update to libgit2 v1.8.4

* Update ordering of CI matrix

* Use new OpenSSH support

Merge pull request #154 from hoerup/libgit2v172

Update libgit2 to v1.7.2

Merge pull request #152 from libgit2/libgit2-171

Update libgit2 to v1.7.1

Merge pull request #149 from arturcic/master

Update libgit2 to v1.6.4

Merge pull request #148 from libgit2/update-ci

Update CI workflow

Merge pull request #145 from libgit2/ethomson/oops_arm64_parameter

Revert "Document the arm64 parameter"

Merge pull request #144 from libgit2/ethomson/v1.6.2

Update libgit2 to v1.6.2

Merge pull request #143 from libgit2/ethomson/v1.6.1

Update libgit2 to v1.6.1

Merge pull request #135 from libgit2/libgit2-update

Update libgit2 to 1.4.2

Merge pull request #124 from libgit2/fix-x86

Force 32-bit Windows build