Add source link

Author: jpenilla

docs/misc/tools/diff-viewer.mdx

@@ -17,3 +17,4 @@ viewer.
 - https://patch-roulette.papermc.io/diff - The diff viewer itself
 - [Chrome Extension](https://chromewebstore.google.com/detail/patch-roulette/feaaoepdocmiibjilhoahgldkaajfnhb)
 - [Firefox Extension](https://addons.mozilla.org/en-US/firefox/addon/patch-roulette/)
+- https://github.com/PaperMC/patch-roulette - Patch Roulette GitHub repository