DRAFT: Add sorting by exclusive label.

[telackey]

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[wxiaoguang]

There are different PRs for this problem and they conflict with each other (and the problem is pending for long time)

• Add advanced labels with priority Add advanced labels with priority #11669

• WIP: Weighted Issues WIP: Weighted Issues #32086

• Issue priority Issue priority #4823

• Add severity/priority feature for issues (Prioritize issues #2616) Add severity/priority feature for issues #2616 #10035