Prefill correct labels in Feedback template

Why is this change being made?

This should make it easier to always use the proper labels, the non-applying ones just have to be removed and then you're done, no need to go through typing ~ and selecting the correct label every time.

Removing the whitespace at the end of the priority line also makes it easier to use, just click at any point in the line after the colon will now pop up the selection list.

Author Checklist

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