Avoid empty extra-arg suggestion spans in macro calls

[TaKO8Ki]

Fixes #152414
Fixes #131762

When building Error::Extra removal suggestions, we extended spans with to and until even when syntax contexts differed in labels_and_suggestion_text. In macro-expanded calls this could fall back to an empty span and triggering an ICE.

I fixed it to combine spans only when contexts match.

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[BoxyUwU]

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