bug#54397: Packages CI link

[Greg Hogan]

Hi,

At https://guix.gnu.org/en/packages/ the "continuous integration system" link to https://ci.guix.gnu.org/jobset/guix-master looks like it should instead reference the "master" jobset.

The "available as pre-built binaries" link references the same, though this could point instead to documentation (perhaps https://guix.gnu.org/manual/en/html_node/Substitutes.html).

Greg