[config][types] Remove duplicate

lib/index.d.ts

@@ -1536,11 +1536,6 @@ declare module 'react-native-firebase' {
          */
         getKeysByPrefix(prefix?: string): Promise<Array<String>>;
 
-        /**
-         * Sets config defaults for parameter keys and values in the default namespace config.
-         */
-        setDefault(defaults: Object): void;
-
         /**
          * Sets the default values from a resource:
          * - Android: Id for the XML resource, which should be in your application's res/xml folder.