[CI] Cleaning self-hosted runners

[CI] Cleaning self-hosted runners

Rationale

There is a need to harden self-hosted runners. Typically there are a few ways to do that:

• Pre/post hook-scripts (https://docs.github.com/en/actions/hosting-your-own-runners/managing-self-hosted-runners/running-scripts-before-or-after-a-job)
• ARC with ephemeral runners enabled
• Volatile VMs with ephemeral runners (just-in-time registration of runners)
• Other inspirational approaches: https://jonico.github.io/awesome-runners/

From my point of view, the first option is the easiest to adopt, just one shell script with passing as an input when running a runner.
ACTIONS_RUNNER_HOOK_JOB_STARTED=cleaning_script.sh ACTIONS_RUNNER_HOOK_JOB_COMPLETED=cleaning_script.sh ./run.sh

Description

API Changes

None, transparent from the workflow point of view.

Implementation details

Depending on the chosen approach, other implementation requirements will be mostly related to the infrastructure setup.

Meta

Start with the linked GitHub Actions documentation on pre- and post-job hooks, then compare that approach with ARC and volatile VMs using the options listed in the issue. Define the infrastructure changes needed to clean self-hosted runners and confirm that workflows remain unchanged after the selected approach is adopted.