docs: fix github docs link (#14787)

Zyqsempai · web-flow · commit e7783f301cea · 2021-09-16T18:55:43.000+02:00
The `https://help.github.com/send-pull-requests/` is not active anymore, it's better ti use this one `https://docs.github.com/en/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request-from-a-fork` and event is more suitable for this particular case.
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -60,4 +60,4 @@ Additional Resources
 
 * [General GitHub documentation](https://help.github.com/)
 
-* [GitHub pull request documentation](https://help.github.com/send-pull-requests/)
+* [GitHub pull request documentation](https://docs.github.com/en/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request-from-a-fork/)

Original file line number	Diff line number	Diff line change
`@@ -60,4 +60,4 @@ Additional Resources`
`60`	`60`
`61`	`61`	`* [General GitHub documentation](https://help.github.com/)`
`62`	`62`
`63`		`-* [GitHub pull request documentation](https://help.github.com/send-pull-requests/)`
	`63`	`+* [GitHub pull request documentation](https://docs.github.com/en/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request-from-a-fork/)`