Add postgres_conn_id to template fields in PostgresOperator

[DucNgn]

Add postgres_conn_id to the template fields for the PostgresOperator

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[hussein-awala]

postgres_conn_id is provided to super as conn_id which is already a template field, I'll test it to decide if it already possible or we need to do it in another way

[hussein-awala]

this can do the job, can you test it?

[hussein-awala]

Suggested change

	template_fields: Sequence[str] = ("sql", "postgres_conn_id")
	template_fields: Sequence[str] = ("sql", "conn_id")

[hussein-awala]

BTW, this operator is deprecated:

airflow/airflow/providers/postgres/operators/postgres.py

Lines 85 to 91 in f20d040

	warnings.warn(
	"""This class is deprecated.
	Please use `airflow.providers.common.sql.operators.sql.SQLExecuteQueryOperator`.
	Also, you can provide `hook_params={'schema': <database>}`.""",
	DeprecationWarning,
	stacklevel=2,
	)

Should we stop updating it?
@potiuk @eladkal

[eladkal]

Should we stop updating it? @potiuk @eladkal

Yes. We do not add new features to deprecated code

[eladkal]

closing in favor of #30784