Improve how TimerDemo.c manages differences between the tick count and its own internal tick count, which can temporarily differ when the tick hook is called while the scheduler is suspended.

FreeRTOS/Demo/Common/Minimal/EventGroupsDemo.c

@@ -326,6 +326,9 @@ EventBits_t uxSynchronisationBit, uxReturned;
 		case. */
 		configASSERT( ( uxReturned & ebALL_SYNC_BITS ) == ebALL_SYNC_BITS );
 
+		/* Remove compiler warning if configASSERT() is not defined. */
+		( void ) uxReturned;
+
 		/* Wait until the 'test master' task unsuspends this task again. */
 		vTaskSuspend( NULL );