[libc++] NFC: Normalize `#endif //` comment indentation

GitOrigin-RevId: 4cd6ca102a94e1b64ba3f940cc26b4d7b2b82964
diff --git a/include/array b/include/array
index 9a479f7..b56fcfe 100644
--- a/include/array
+++ b/include/array
@@ -520,4 +520,4 @@
 
 _LIBCPP_END_NAMESPACE_STD
 
-#endif  // _LIBCPP_ARRAY
+#endif // _LIBCPP_ARRAY