Scroll to "show test networks" setting from network dropdown link (#12711)

* Scroll to "show test networks" setting from network dropdown link

* Focusing element

ui/components/app/dropdowns/network-dropdown.js

@@ -324,7 +324,7 @@ class NetworkDropdown extends Component {
                   onClick={(e) => {
                     e.preventDefault();
                     hideNetworkDropdown();
-                    history.push(ADVANCED_ROUTE);
+                    history.push(`${ADVANCED_ROUTE}#show-testnets`);
                   }}
                 >
                   {t('here')}

ui/pages/settings/advanced-tab/advanced-tab.component.js

@@ -61,6 +61,15 @@ export default class AdvancedTab extends PureComponent {
     showLedgerTransportWarning: false,
   };
 
+  showTestNetworksRef = React.createRef();
+
+  componentDidMount() {
+    if (window.location.hash.match(/show-testnets/u)) {
+      this.showTestNetworksRef.current.scrollIntoView({ behavior: 'smooth' });
+      this.showTestNetworksRef.current.focus();
+    }
+  }
+
   renderMobileSync() {
     const { t } = this.context;
     const { history } = this.props;
@@ -234,6 +243,7 @@ export default class AdvancedTab extends PureComponent {
 
     return (
       <div
+        ref={this.showTestNetworksRef}
         className="settings-page__content-row"
         data-testid="advanced-setting-show-testnet-conversion"
       >