fixing CONTRIBUTING.md and updating it to new URL

CONTRIBUTING.md

@@ -1,6 +1,6 @@
-<!--
-SPDX-FileCopyrightText: 2018 yuzu Emulator Project
-SPDX-License-Identifier: GPL-2.0-or-later
--->
-
-**The Contributor's Guide has moved to [the yuzu wiki](https://github.com/yuzu-emu/yuzu/wiki/Contributing).**
+<!--
+SPDX-FileCopyrightText: 2018 yuzu Emulator Project
+SPDX-License-Identifier: GPL-2.0-or-later
+-->
+
+**The Contributor's Guide has moved to [the suyu wiki](https://gitlab.com/suyu2/suyu/-/wikis/home).**