Remove stale type-ignore TODO in HTTP hook run_with_advanced_retry

[ed-kyu]

HttpHook.run_with_advanced_retry carried a TODO asking to remove a # type: ignore once tenacity#428 is resolved:

# TODO: remove ignore type when https://github.com/jd/tenacity/issues/428 is resolved
return self._retry_obj(self.run, *args, **kwargs)  # type: ignore

However, the # type: ignore itself was already removed in #53294 (Cleanup type ignores) — but that PR left the accompanying TODO comment behind. The comment now points at an ignore that no longer exists, so it is pure leftover noise. This PR removes the stale comment.
No functional or type-checking change: the # type: ignore has been absent since #53294 and mypy passes on main without it.

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• Yes

Generated-by: Claude Code (Opus 4.8) following the guidelines

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