unused_labels should be reported as warnings #66324
Description
A long while back there was Issue #50751 which pointed out that the compiler was not linting for unused break labels. This resulted after a lot of fantastic hard work in PR #50763 which added the unused_labels lint.
At the time, the lint was set to allow by default. The consensus was that there would need to be a review and a crater run before it was changed to warn. Issue #50751 was closed without this happening, and this is where we stand today.
I'd love to see this changed to warn by default. Any chance that could happen?