Updated to actions/labeler@v5
Updated labeler config accordingly, also improved the config and added
more labels.
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Co-authored-by: Giteabot <teabot@gitea.io>
Alternative to https://github.com/go-gitea/gitea/pull/27439. Removes a
few spammy labels, and disables `sync-labels` which make it never remove
labels (which is default behaviour).