Enable deduplication of unofficial reviews. When pull requests are
configured to include all approvers, not just official ones, in the
default merge messages it was possible to generate duplicated
Reviewed-by lines for a single person. Add an option to find only
distinct reviews for a given query.
fixes#24795
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Signed-off-by: Cory Todd <cory.todd@canonical.com>
Co-authored-by: Giteabot <teabot@gitea.io>