repos: enable CSR mirroring for x/pkgsite
repos: enable CSR mirroring for x/pkgsite

Change-Id: I82111c4442aa4b711bedfb9aad43c59ff663d0a9
Reviewed-on: https://go-review.googlesource.com/c/build/+/360721
Trust: Jamal Carvalho <e0195770807aa8c82b0b128d9c0423b5ad035172@golang.org>
Run-TryBot: Jamal Carvalho <e0195770807aa8c82b0b128d9c0423b5ad035172@golang.org>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>

golang/build,golang/build,golang/build,golang/build