Enable coroutine context for invoking config method of a handler in coroutine mode

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So far, the call of the configuration function, viz. handler.config(map), in the coroutine mode has not enabled the coroutine context, so in this case, if we perform some database initialization operations in the configuration function, these operations will be executed with the Java default socket instead of the coroutine socket. It may cause some problems, especially in the case of socket connection pool.
This feature will enable coroutine context for configuration functions in coroutine mode.