Auto merge of rust-lang#9245 - alex-semenyuk:enable_multiple_config_files_on_windows, r=Alexendoo

Enable test multiple_config_files on windows

Verified that it actully works on windows
changelog: none

Author: bors

tests/ui-cargo/multiple_config_files/warn/src/main.rs

@@ -1,5 +1,3 @@
-// ignore-windows
-
 fn main() {
     println!("Hello, world!");
 }