feat: PR comment actions

Description

This MR implements GitHub PR comment based pipeline triggering.

Supporting information

https://tasks.opencraft.com/browse/SE-6031

Testing instructions

Check the following pages and comment/pipeline pairs. The pipelines are failing at the moment due to a bash issue, though that's out of scope here as we are curious about pipeline creation (not state).

Events:

• https://github.com/open-craft/edx-platform/settings/hooks/434082134?tab=deliveries

Destroy

• Comment: https://github.com/open-craft/edx-platform/pull/554#issuecomment-1723147118 
• Destroy pipeline: https://gitlab.com/opencraft/ops/grove-stage-digitalocean/-/pipelines/1008202745

Create

• Comment: https://github.com/open-craft/edx-platform/pull/554#issuecomment-1723154597
• Create pipeline: https://gitlab.com/opencraft/ops/grove-stage-digitalocean/-/pipelines/1008207536

Update

• Comment: https://github.com/open-craft/edx-platform/pull/554#issuecomment-1723156567
• Update pipeline: https://gitlab.com/opencraft/ops/grove-stage-digitalocean/-/pipelines/1008209756

Dependencies

This MR builds on top of !222 (merged).

Screenshots

N/A

Checklist

If any of the items below is not applicable, do not remove them, but put a check in it.

• All providers include the new feature/change
• All affected providers can provision new clusters
• Unit tests are added/updated
• Documentation is added/updated
• The TOOLS_CONTAINER_IMAGE_VERSION in ci_vars.yml is updated
• The grove-template repository is updated

Additional context

Add any other context about the merge request here.