fix: remove deprecated event listener method from appearance.js (face…

…book#32526)

Summary:
Remove unused deprecated event listener method from appearance.js

## Changelog

[General] [Removed] - Remove deprecated removeListener from Appearance that causes deprecation message in log box.

Pull Request resolved: facebook#32526

Reviewed By: cortinico

Differential Revision: D35287187

Pulled By: yungsters

fbshipit-source-id: cf0af61ed8636855aa625579e27816a6c10b6b81

Libraries/Utilities/Appearance.js

@@ -93,12 +93,4 @@ module.exports = {
   addChangeListener(listener: AppearanceListener): EventSubscription {
     return eventEmitter.addListener('change', listener);
   },
-
-  /**
-   * @deprecated Use `remove` on the EventSubscription from `addEventListener`.
-   */
-  removeChangeListener(listener: AppearanceListener): void {
-    // NOTE: This will report a deprecation notice via `console.error`.
-    eventEmitter.removeListener('change', listener);
-  },
 };