Synchronization updated thanks to GitHub Actions.

Author: Francisco-G-P

twin/README.md

@@ -117,14 +117,14 @@ public class BallThread extends Thread {
 
   public synchronized void resumeMe() {
     isSuspended = false;
-    notify();
+    notifyAll();
     LOGGER.info("Resuming BallThread");
   }
 
   public synchronized void stopMe() {
     isRunning = false;
     isSuspended = false;
-    notify();
+    notifyAll();
   }
 }
 ```

twin/src/main/java/com/iluwatar/twin/BallThread.java

@@ -77,13 +77,13 @@ public synchronized void suspendMe() {
 
   public synchronized void resumeMe() {
     isSuspended = false;
-    notify(); // Wakes up the thread from waiting state.
+    notifyAll(); // Wakes up the thread from waiting state (prevents lost wake-ups).
     LOGGER.info("Resuming BallThread");
   }
 
   public synchronized void stopMe() {
     isRunning = false;
     isSuspended = false;
-    notify(); // Makes sure the thread wakes up and exits (stops).
+    notifyAll(); // Makes sure the thread wakes up and exits (prevents lost wake-ups).
   }
 }