Update libgit2sharp to 0.24+ to fix path issues with escape sequences

[nlowe]

libgit2sharp can't load the native DLL if the path contains %2F, which happens frequently on Jenkins when building pipelines in nested folders.

libgit2/libgit2sharp#1389 was fixed in libgit2/libgit2sharp#1409, which appears to be in 0.24+. It looks like GitVersion master is still targeting a prerelease of 0.23. Any chance we can upgrade to 0.24+ and cut a release? I'd be happy to send a PR if that is acceptable.

We can work around this by setting a customWorkspace on the Jenkins node definition, but I'd really like to not have to update all my builds with custom workspace naming logic just to get nice versioning.

[nlowe]

It seems like #1248 may solve this.

[asbjornu]

After upgrading to LibGit2Sharp 0.26 in #1713, I hope this problem is fixed. Please try the latest build of GitVersion and report back whether it fixes this problem or not. Reopen this issue if the problem persists.