test: Add some ungenerated documentation

packages/cozy-client/src/CozyClient.js

@@ -1719,6 +1719,12 @@ instantiation of the client.`
     return reducer
   }
 
+  /**
+   * Dispatches an action to the Redux store.
+   *
+   * @param {Object} action - The action to be dispatched.
+   * @returns {Object} The dispatched action.
+   */
   dispatch(action) {
     return this.store.dispatch(action)
   }