Fix app-files acceptance tests

Signed-off-by: Louis Chemineau <louis@chmn.me>

tests/acceptance/features/bootstrap/FilesAppContext.php

 	 * @return Locator
 	 */
 	public static function notFavoritedStateIconInFileDetailsInDetailsView() {
-		return Locator::forThe()->css(".icon-star")->
+		return Locator::forThe()->css(".star--star")->
 				descendantOf(self::favoriteActionInFileDetailsInDetailsView())->
 				describedAs("Not favorited state icon in file details in details view in Files app");
 	}
 	 * @return Locator
 	 */
 	public static function favoritedStateIconInFileDetailsInDetailsView() {
-		return Locator::forThe()->css(".icon-starred")->
+		return Locator::forThe()->css(".star--starred")->
 				descendantOf(self::favoriteActionInFileDetailsInDetailsView())->
 				describedAs("Favorited state icon in file details in details view in Files app");
 	}