When filtering a label yields a result, we should hide the "No label" option
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Showing "No label" in this case doesn't make sense -- the user has entered text _specifically to find a label_.
Going further to improve the UX, if the user is filtering and we're down to a single result, I think it should be highlighted automatically. In this case I should be able to just type "test" and hit <kbd>Enter</kbd> without first highlighting it.
issue