x/pkgsite: move source links to GitHub

[ghost]

this was previously discussed, but not in the scope of raw links.

What is the URL of the page with the issue?

https://pkg.go.dev/fmt#Println

What is your user agent?

Screenshot

What did you do?

I followed the link above to the linked source:

https://cs.opensource.google/go/go/+/go1.20.6:src/fmt/print.go

What did you expect to see?

if I visit the same file on GitHub:

https://github.com/golang/go/blob/go1.20.6/src/fmt/print.go

a Raw link is available:

https://raw.githubusercontent.com/golang/go/go1.20.6/src/fmt/print.go

What did you see instead?

I do not see any any such Raw link on cs.opensource.google.

[seankhliao]

Duplicate of #44829

[ghost]

that was two years ago, and has no discussion of raw links.

thanks again for your valuable work on the issue tracker.