Add info about checks and extra_checks
To try to resolve #8 (closed), this MR attempts to improve the documentation for how to define checks in info.yaml
. This adds a clearer description of how exactly to define which checks will be run for each job, and adds a mention of the extra_checks
option (which was previously missing).
Work related to https://gitlab.cern.ch/lhcb-dpa/project/-/issues/93