Define policies for jenkins job retention to ensure adequate disk space management

[sxa]

Spin off from #2108

On the jenkins server there is quite a mix of policies in place regarding how long jobs are retained for, and how long the artefacts are retained for. In many cases the job logs aren't too much of a problem (but will build up over time as I recently saw with VagrantPlaybookCheck) but artefact management can be more critical as left unchecked it will consume quite a lot of space on the jenkins server.

We should also look at the policy around "locked" jobs and whether we need to retain them indefinitely (e.g. production build pipelines) and potentially audit any other jobs that people have locked.

[sxa]

Related: adoptium/ci-jenkins-pipelines#895 which will potentially have an impact on space requirements