[examples] Prepare for RobotInit deprecation by updating examples (#6623)

Co-authored-by: Tyler Veness <calcmogul@gmail.com>

wpilibj/src/test/java/edu/wpi/first/wpilibj/TimedRobotTest.java

@@ -45,10 +45,7 @@ class TimedRobotTest {
 
     MockRobot() {
       super(kPeriod);
-    }
 
-    @Override
-    public void robotInit() {
       m_robotInitCount.addAndGet(1);
     }