Use correct clientSecret param in refresh

Author: itaym2

android/src/main/java/com/reactlibrary/RNAppAuthModule.java

@@ -354,7 +354,7 @@ public void onTokenRequestCompleted(@Nullable TokenResponse response, @Nullable
 
 
         if (clientSecret != null) {
-            ClientAuthentication clientAuth = new ClientSecretBasic(this.clientSecret);
+            ClientAuthentication clientAuth = new ClientSecretBasic(clientSecret);
             authService.performTokenRequest(tokenRequest, clientAuth, tokenResponseCallback);
 
         } else {