fix: issue 675：goroutine leak when connectionUp(true) return error

[kiqi007]

bug: #675

fix:
···
if err := connectionUp(true); err != nil {
ERROR.Println(CLI, err)

	/* issue 675：goroutine leak when connectionUp(true) return error
	 *   Only when status == disconnecting will this logic be executed.
	 * The goroutine that changes the status to disconnecting should be
	 * responsible for resource cleanup (which is indeed how it is done).
	 *
	 *   Being disconnected right when the connection is established is a special case.
	 * Even if we remove this check for connectionUp(true), the program must still function correctly,
	 * as if a Disconnect event occurred immediately after connectionUp(true) completed.
	 */

	//close(c.stop) // Tidy up anything we have already started
	//close(incomingPubChan)
	//c.workers.Wait()
	//c.conn.Close()
	//c.conn = nil
}

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