While working on https://github.com/apache/airflow/pull/52129/files, i saw this pattern in many places.

Pattern of this type:

    @provide_session
    def setup_method(self, method, session=None):
        conn = session.query(Connection).filter(Connection.conn_id == DEFAULT_CONN_ID).first()
        conn.host = HOST
        conn.schema = None
        conn.port = None
        conn.login = None
        conn.password = None
        conn.extra = json.dumps({"token": TOKEN, "host": HOST})

        session.commit()

        self.hook = DatabricksHook()

We should not be overriding default connections this way at ALL, it will make migration of providers to use task sdk extremely hard / annoying. Cleaning up that pattern to use the fixture introduced in #51930

I am introducing a way for tests to only use connections from env via #52129, which will follow this one

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