[docs] Use a go/ link for the internal design docs folder.

This avoids the problem of random people requesting access
to the internal drive folder.

Bug: none
Change-Id: I086069dd55d208237f5db53fce31e295698acd6d
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5969934
Auto-Submit: Benedikt Meurer <[email protected]>
Commit-Queue: Simon Zünd <[email protected]>
Reviewed-by: Simon Zünd <[email protected]>

Author: bmeurer

docs/contributing/design.md

@@ -39,7 +39,7 @@ be send to
 [[email protected]](mailto:[email protected]).
 
 Google internal design docs have to live in the
-[Design Documents (internal)](https://drive.google.com/corp/drive/folders/15oHN9vX8j08QOkegjWKdSN0XjyaoLanl)
+[Design Documents (internal)](http://go/chrome-devtools:design-internal-drive)
 folder of the shared internal
 [Chrome DevTools](http://go/chrome-devtools/team-resources#chrome-devtools-shared-drive) team drive, and
 should be sent to