Fix it doesn't play well with trivia when expanded in test 'testEnumInstanceFunction()'

Specifically for diagnostic 'Cannot create a test for instance functions on types that cannot be initialised'

Start with the testEnumInstanceFunction() test and reproduce the diagnostic “Cannot create a test for instance functions on types that cannot be initialised” while the expansion includes trivia. Inspect how the expanded test and diagnostic interact, then verify that the diagnostic remains correct after the fix.

Rédigé par le modèle d'indexation à partir du texte de l'issue.