chore: move health check into package itself (#183)

## Description

This moves the health check waits into the package itself to avoid race
conditions with other components that may want to talk to GitLab (i.e.
GitLab Runner)

## Related Issue

Fixes #N/A

## Type of change

- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [X] Other (security config, docs update, etc)

## Checklist before merging

- [X] Test, docs, adr added or updated as needed
- [X] [Contributor Guide
Steps](https://github.com/defenseunicorns/uds-package-gitlab/blob/main/CONTRIBUTING.md#developer-workflow)
followed