undo fix of false positive from docs-differ (#2708)

Author: ktabors

packages/@react-aria/ssr/docs/useIsSSR.mdx

@@ -50,5 +50,5 @@ import {useIsSSR} from '@react-aria/ssr';
 function MyComponent() {
   let isSSR = useIsSSR();
   return <span>{isSSR ? 'Server' : 'Client'}</span>;
-};
+}
 ```