Dismiss keyboard on menu open

react/features/welcome/components/WelcomePage.native.js

 import React from 'react';
 import {
+    Keyboard,
     SafeAreaView,
     Switch,
     TextInput,
      * @returns {void}
      */
     _onShowSideBar() {
+        Keyboard.dismiss();
         this.props.dispatch(setSideBarVisibility(true));
     }