[MM-20742] Null checking on URL pathname when deep linking (#1243)

* [MM-20742] Null checking on URL pathname when deep linking

* Switched to using '/' instead of blank string

src/browser/components/MainPage.jsx

@@ -70,8 +70,8 @@ export default class MainPage extends React.Component {
             teamURL,
             teamIndex: index,
             originalURL: deeplinkURL,
-            url: `${teamURL.protocol}//${teamURL.host}${deeplinkURL.pathname}`,
+            url: `${teamURL.protocol}//${teamURL.host}${deeplinkURL.pathname || '/'}`,
-            path: deeplinkURL.pathname,
+            path: deeplinkURL.pathname || '/',
           };
         }
       });