DEPS: Clean unused dependencies
* When installing pytables, it appears `blosc2` is generally a dependency now https://github.com/PyTables/PyTables/blob/9afcc380d93192460e7badd1baf568592cadad26/pyproject.toml#L78
* I don't think we use `google-auth` or `gitdb` anywhere now
Looks good, I guess xarray was pinned to not allow the latest versions because of the test failures in the CI.

@shoyer @FrancescAlted if you have any comment here... Since this PR is green, going to merge. Happy to follow up if needed