internal/fetch/dochtml/internal/render: point to CL 72890
The previous CL wasn't the right one to point to.
// Package render formats Go documentation as HTML.
//
-// This is a temporary copy of CL 94855 (golang.org/cl/94855) for
+// This is a temporary copy of CL 72890 (golang.org/cl/72890) for
// testing of and iteration on its implementation and design.
// It doesn't need to be updated other than as part of work on
// b/137567588. Please /cc dmitshur@ on all changes to it.
