Make HttpSensor defer when response_check is provided

[yuseok89]

closes: #40209

HttpSensor(deferrable=True) with a response_check silently fell back to the synchronous poke loop, occupying a worker slot for the whole wait. It now defers like any other deferrable sensor: the triggerer waits for the endpoint to respond without error, the check runs on the worker, and if it returns False the task defers again, keeping the poke_interval pacing.

The callable stays on the worker; only the response is carried back, reusing the JSON serializer already in triggers/http.py. This is the same pattern S3KeySensor uses for check_fn.

Verified with a live Dag

An HttpSensor(deferrable=True, poke_interval=20) polling this Airflow's own api-server, with a response_check that only passes two minutes after the run was triggered.

Before the change the task never left running, since a response_check forced it onto the synchronous path.
After the change it goes straight to deferred, wakes every 20 seconds to evaluate the check on the worker, and succeeds once the check passes:

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  • Opus 4.8

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