code cleanup

Author: yatharthranjan

kafka-connect-fitbit-source/src/main/java/org/radarbase/connect/rest/fitbit/user/firebase/FirebaseUserRepository.java

@@ -13,7 +13,6 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
-import javax.ws.rs.NotAuthorizedException;
 import org.radarbase.connect.rest.RestSourceConnectorConfig;
 import org.radarbase.connect.rest.fitbit.user.UserRepository;
 import org.slf4j.Logger;
@@ -81,7 +80,7 @@ protected DocumentSnapshot getDocument(String key, CollectionReference collectio
    * @param object The POJO to write to the document
    * @throws IOException If there was a problem updating the document
    */
-  protected synchronized void updateDocument(DocumentReference documentReference, Object object)
+  protected void updateDocument(DocumentReference documentReference, Object object)
       throws IOException {
     try {
       documentReference.set(object, SetOptions.merge()).get(20, TimeUnit.SECONDS);

kafka-connect-fitbit-source/src/main/java/org/radarbase/connect/rest/fitbit/user/firebase/FitbitTokenService.java

@@ -76,7 +76,7 @@ public FitbitOAuth2UserCredentials processTokenRequest(FormBody form)
     }
   }
 
-  public synchronized FitbitOAuth2UserCredentials refreshToken(String oldToken) throws IOException {
+  public FitbitOAuth2UserCredentials refreshToken(String oldToken) throws IOException {
     FormBody form =
         new FormBody.Builder()
             .add("grant_type", "refresh_token")