Honor async hook subclass overrides in get_async_connection

[anxkhn]

get_async_connection resolved the connection through the literal BaseHook
class, so a hook that overrides aget_connection/get_connection was ignored in
the triggerer even though the sync path honors it on the worker.

The sync path dispatches through the instance: provider hooks call
self.get_connection(...) (e.g. HttpHook), so a subclass override wins. The
async path called the module helper, which hard-coded BaseHook.aget_connection
and only took a conn_id, so it could never see a subclass override. A user who
subclasses HttpAsyncHook and overrides aget_connection to inject
host/login/etc. gets correct fields on the worker but empty fields in the
triggerer.

This adds an optional hook parameter so the helper dispatches through the
calling hook (defaulting to BaseHook, so all existing callers are unchanged),
and passes the hook from HttpAsyncHook. Custom subclasses now behave the same
in the triggerer as on the worker.

This reopens the fix from #67440, which was closed only as inactive-draft
housekeeping (not on its merits); this PR is rebased on the latest main and
ready for review.

closes: #66845

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[SameerMesiah97]

Looks fine. Just needs a few adjustments.

Please fix CI as well.

[anxkhn]

Thanks for the review, all four addressed:

1. Log message: both branches now log the actual resolving hook via %s. I compute the name as hook.__name__ if isinstance(hook, type) else type(hook).__name__ rather than a bare hook.__name__, since points 2 and 3 let hook be an instance and a bare .__name__ would raise on instances.
2. Typing: widened to BaseHook | type[BaseHook] | None.
3. type(self) -> self: switched to self; the helper handles an instance throughout, and passing the instance preserves instance-specific behavior, which is the worker/triggerer parity this PR is after.
4. Added test_get_async_connection_honors_passed_hook_get_connection, mirroring the async one; it exercises the sync_to_async branch and fails without the fix.

ruff, ruff-format, mypy, and the compat connection test module pass locally.

[dabla]

@anxkhn Check the ci/cd failure, yoiu need to add the # use next version, think we are almost there.