enforce required imports even with useless alias (#14287)
This PR handles a panic that occurs when applying unsafe fixes if a user
inserts a required import (I002) that has a "useless alias" in it, like
`import numpy as numpy`, and also selects PLC0414 (useless-import-alias)
In this case, the fixes alternate between adding the required import
statement, then removing the alias, until the recursion limit is
reached. See linked issue for an example.
Closes #14283
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Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>
