Show which test failed and in which configuration

[marcoieni]

Right now, rla only shows which job failed. It would be nice to also show which test failed and on which configuration.

Note that sometimes this information is not available (eg because the job failed outside of the "run the build" CI step). So this should be a best effort implementation.

Original infra survey comment:

When CI fails, it's often not easy to figure out which exact test suite failed in which configuration (in particular, on which target!), and how to reproduce the failure locally. (I guess that's more of a t-bootstrap than t-infra thing?)