Fix LivyAsyncHook sending POST to Livy GET only endpoints

[Jie211]

LivyAsyncHook.get_batch_state() and get_batch_logs() call run_method() without specifying method,
so they fall back to self.method, which LivyAsyncHook.__init__ hardcodes to "POST".

Livy only accepts GET on /batches/{id}/state and /batches/{id}/log,
so both requests fail with 405 Method Not Allowed.

If i use deferrable mode, the batch is submitted, but the first poll from the trigger fails.

    WARNING  [Try 1 of 3] Request to https://<livy>:8998/batches/<id>/state failed.
    {"Response": ["Method Not Allowed"], "Status Code": [405], "status": "error"}
    AirflowException: Batch <id> did not succeed with 'str' object has no attribute 'value'

Maybe this is come from this PR: #60458

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[Nataneljpwd]

Looks good to me

[eladkal]

cc @dabla for review after #60458