_content/ref: update ref/mod for workspaces
_content/ref: update ref/mod for workspaces

Add entries for go.work files and the new go work commands to
golang.org/ref/mod.

For golang/go#45713

Change-Id: I1ad3335f977fad864d75790e31e48ee34e531ff5
Reviewed-on: https://go-review.googlesource.com/c/website/+/379655
Reviewed-by: Bryan Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
Trust: Michael Matloob <1b6ee578db4d95965bf73831a3b5b715e4ec96c4@gmail.com>

golang/website,golang/website,golang/website,golang/website,golang/website,golang/website,golang/website