Fixes#36727
Git is lowercasing the `fatal: Not a valid object name` error message
to follow its CodingGuidelines. This change makes the string matching
case-insensitive so it works with both the current and future Git
versions.
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
This module is merged from https://github.com/go-gitea/git which is a Go module to access Git through shell commands. Now it's a part of gitea's main repository for easier pull request.