[FSSDK-11138] config parser update

Author: junaed-optimizely

OptimizelySDK/Utils/ConfigParser.cs

@@ -33,7 +33,13 @@ public static Dictionary<string, T> GenerateMap(IEnumerable<T> entities,
             Func<T, string> getKey, bool clone
         )
         {
-            return entities.ToDictionary(e => getKey(e), e => clone ? (T)e.Clone() : e);
+            var dictionary = new Dictionary<string, T>();
+            foreach (var entity in entities)
+            {
+                var key = getKey(entity);
+                dictionary[key] = clone ? (T)entity.Clone() : entity;
+            }
+            return dictionary;
         }
     }
 }