Add test for mis-annotated method

Previously, if a method:
  1. was annotated with @EnforcePermission,
  2. belonged to a class which implements an AIDL interface,
  3. but did not override a method from that interface;
an error was returned as the call to the helper was missing. The correct
error for this case is that the method should not use the annotation.
Update the detector and add a test for this case.

Bug: 307433823
Test: atest --host AndroidGlobalLintCheckerTest
Change-Id: I04c68e95bc4932459b46982a7dd1814424ff6b46