Add gitlab version exporter

What does this MR do?

This MR implements a couple of cron jobs that write omnibus & GitLab component version info into the textfile collector directory for node-exporter. We do this in staging & production and these variables are used in dashboards like the delivery release management dashboard.

I'm not 100% sure we want this in GET as users may not care for this metric. There are many ways to implement this in Ansible so this is a proposal that we can iterate on.

I've tested this and it works fine in staging-ref, however it hasn't been tested in RHEL.

@gl-quality/eng-prod < not sure if this is the right group to mention as @gl-quality/get-maintainers doesn't seem to exist anymore.

Related issues

https://gitlab.com/gitlab-com/gl-infra/infrastructure/-/issues/15138

Author's checklist

When ready for review, the Author applies the workflowready for review label and mention @gl-quality/get-maintainers:

• Merge request:
  • Corresponding Issue raised and reviewed by the GET maintainers team.
  • Merge Request Title and Description are up to date, accurate, and descriptive
  • MR targeting the appropriate branch
  • MR has a green pipeline
• Code:
  • Check the area changed works as expected. Consider testing it in different environment sizes (1k,3k,10k,etc.).
  • Documentation created/updated in the same MR.
  • If this MR adds an optional configuration - check that all permutations continue to work.
  • For Terraform changes: setup a previous version environment, then run a terraform plan with your new changes and ensure nothing will be destroyed. If anything will be destroyed and this can't be avoided please add a comment to the current MR.
• Create any follow-up issue(s) to support the new feature across other supported cloud providers or advanced configurations. Create 1 issue for each provider/configuration. Contact the Quality Enablement team if unsure.