Fix the broken xcode detection due to space

Summary: Due to the space in the path, `fs.pathExists` returned false even if the path was existent. Thus added `.trim()` to fix it.

Reviewed By: passy

Differential Revision: D26869404

fbshipit-source-id: 146a96262353177e786f5100a1dad9af7c7d398b

desktop/app/src/utils/iOSContainerUtility.tsx

@@ -262,7 +262,7 @@ function wrapWithErrorMessage<T>(p: Promise<T>): Promise<T> {
 async function isXcodeDetected(): Promise<boolean> {
   return exec('xcode-select -p')
     .then(({stdout}) => {
-      return fs.pathExists(stdout);
+      return fs.pathExists(stdout.trim());
     })
     .catch((_) => false);
 }