Switch to github hosted runners for host image promote

[jovial]

So we can promote images now that SMS lab is down.

[jovial]

Failing with:

Run BRANCH=$(awk -F'=' '/defaultbranch/ {print $2}' .gitreview)
awk: fatal: cannot open file `.gitreview' for reading: No such file or directory
Error: Process completed with exit code 2.

investigating...

[markgoddard]

Failing with:

Run BRANCH=$(awk -F'=' '/defaultbranch/ {print $2}' .gitreview)
awk: fatal: cannot open file `.gitreview' for reading: No such file or directory
Error: Process completed with exit code 2.

investigating...

It's because SKC is checked out at src/kayobe-config. Looks like we might have been relying on a previous run's checkout, which could have contained anything...

[jovial]

Thanks, seems to do the business: https://github.com/stackhpc/stackhpc-kayobe-config/actions/runs/7814044183/job/21314453693

[jovial]

I've rebased this on yoga (as requested by @markgoddard)