Update libgit2 to 1.8.0

[fxcoudert]

According to the release notes, three breaking (ABI) changes are handled here:

• GIT_CONFIG_LEVEL_WORKTREE constant (and modification to value of GIT_CONFIG_LEVEL_APP)
• git_config_entry structure
• git_push_options structure

https://github.com/libgit2/libgit2/releases/tag/v1.8.0

[fxcoudert]

One thing I don't understand is: why does stdlib/LibGit2/Project.toml say:

name = "LibGit2"
uuid = "76f85450-5226-5b5a-8eaa-529ad045b433"
version = "1.11.0"

The version is not the same for LibGit2_jll and LibGit2. Where does that LibGit2 version come from? And what does that mean for checks like if LibGit2.VERSION >= v"1.8.0", meaning, are they actually correct or not?

[fxcoudert]

• x86_64-w64-mingw32 looks a lot like that in zlib PR: Update zlib to 1.3.1 #53841
• x86_64-linux-gnuprofiling is a timeout

Is testing expected to be clean?

[KristofferC]

One thing I don't understand...

This is the version of the julia package LibGit2 that wraps the libgit2 library. Stdlibs usually had no versions but this was awkward so in 1.11 they where somewhat arbitrarily assigned the version of the current julia version. LibGit2.VERSION is unrelated to this value.

[fxcoudert]

Then I think this is ready to merge