Spike: Investigate the best pipeline definition for Workspaces

MR: Pending

Description

To create Workspaces on CI Runners, we need to decide what the CI pipeline definition for this would look like, what executor will we use, etc. This spike issue is to document the different approaches we can take with the CI definition, the pros/cons of each and decide on how to proceed from there.

The problem was discussed in this Workspaces Engineering Sync on 2025/03/06 - https://youtu.be/nvX_yjStRe4

Acceptance criteria

• A matrix/list of what features we can achieve using a given executor and using the given CI YAML syntax. Each approach should be measured against the existing and upcoming features, planned requirements and future requirements. It should also be measured against how widely a given executor is adopted. We would like for the feature to be as widely available as possible.
• Pro/Con of each approach in the matrix/list.

Implementation plan

N.A.