Clean up Java warning suppressions (#4433)

Checkstyle naming conventions were changed to allow most of what's in
wpimath. Naming rules were disabled completely in wpimath since almost
all suppressions are for math notation.

wpilibjIntegrationTests/src/main/java/edu/wpi/first/wpilibj/MockDS.java

@@ -22,7 +22,7 @@ public class MockDS {
     data[5] = 0x00; // red 1 station
   }
 
-  @SuppressWarnings("MissingJavadocMethod")
+  /** Start the mock DS thread. */
   public void start() {
     m_thread =
         new Thread(
@@ -67,7 +67,7 @@ public class MockDS {
     m_thread.start();
   }
 
-  @SuppressWarnings("MissingJavadocMethod")
+  /** Stop the mock DS thread. */
   public void stop() {
     if (m_thread == null) {
       return;