[java] Deprecate CDP support for FirefoxDriver

Author: pujagani

java/src/org/openqa/selenium/firefox/FirefoxDriver.java

@@ -291,6 +291,7 @@ public Optional<DevTools> maybeGetDevTools() {
   /**
    * @deprecated Use W3C-compliant BiDi protocol. Use {{@link #getBiDi()}}
    */
+  @Deprecated
   @Override
   public DevTools getDevTools() {
     if (!cdpUri.isPresent()) {