Fix UIExplorer example AppDelegate.m for pre-bundle comment

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UIExplorer example doc fix.

**Test plan (required)**

Unnecessary.

**Code formatting**

Just fix comment, not related to code

Fix pre-bundle doc
Closes #8733

Differential Revision: D3554930

fbshipit-source-id: 76ed3da17df840f90987f7468cea7cd65741313f

Author: 弘树

Examples/UIExplorer/UIExplorer/AppDelegate.m

@@ -74,7 +74,7 @@ - (NSURL *)sourceURLForBridge:(__unused RCTBridge *)bridge
      * Load from pre-bundled file on disk. To re-generate the static bundle, `cd`
      * to your Xcode project folder and run
      *
-     * $ curl 'http://localhost:8081/Examples/UIExplorer/UIExplorerApp.ios.bundle?platform=ios' -o main.jsbundle
+     * $ curl 'http://localhost:8081/Examples/UIExplorer/js/UIExplorerApp.ios.bundle?platform=ios' -o main.jsbundle
      *
      * then add the `main.jsbundle` file to your project and uncomment this line:
      */