bump-formula-pr: remove unnecessary newlines

[botantony]

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Follow-up to #21658, these newlines are not trimmed

[Copilot]

Pull request overview

This PR adjusts the generated PR body content for brew bump-formula-pr by removing extra blank lines before the newly added “TODO/FIXME checked” checklist item (follow-up to #21658).

Changes:

• Removes leading blank lines before the “TODO and FIXME comments have been checked.” checkbox in the bump PR message template.

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[MikeMcQuaid]

Thanks! One comment.

[MikeMcQuaid]

Thanks!