add useEmulator to compat

Author: jhuleatt

packages/remote-config-compat/src/remoteConfig.ts

@@ -35,7 +35,8 @@ import {
   getNumber,
   getString,
   getValue,
-  isSupported
+  isSupported,
+  connectRemoteConfigEmulator
 } from '@firebase/remote-config';
 
 export { isSupported };
@@ -73,6 +74,10 @@ export class RemoteConfigCompatImpl
     return activate(this._delegate);
   }
 
+  useEmulator(url: string): void {
+    connectRemoteConfigEmulator(this._delegate, url);
+  }
+
   ensureInitialized(): Promise<void> {
     return ensureInitialized(this._delegate);
   }