Update Unity package versions.

Change-Id: If5426bc70db961e5083b7e3d7944841a5ac08a14

Author: dzlier-gcp

Firebase_RemoteConfig/Scripts/RemoteConfigSyncBehaviour.cs

@@ -19,7 +19,6 @@ limitations under the License.
 using System;
 using System.Collections;
 using System.Collections.Generic;
-using System.Linq;
 using UnityEngine;
 
 namespace Firebase.ConfigAutoSync {