Adds necessary repo configs for Workspaces feature

What does this MR do and why?

• This creates the very basics of enabling the Workspaces feature for `release-tools
• The GitLab Agent will be leveraged to connect a Kubernetes cluster to our Repo for what could be a wide array of reasons, but in our case, only enabling this for Workspaces
  • I've created the necessary infrastructure for testing, hence the use of a non-GitLab domain
  • Should we decide to keep Workspaces around, we can rework this to bring online an agent using a better domain
  • Adding a cluster to our repo is required for the Workspaces feature
• Adds a skeleton devfile
  • Only using the golang image for the sake of playing around and validating we can successfully stand up a workspace
  • Uses default values from an example file for Pod resource limits
  • Should we decide to keep Workspaces around, we can build a better Docker image for us to leverage and bring in the necessary tooling that we need for release-tools

More about Workspaces:

• https://about.gitlab.com/blog/2023/05/23/introducing-workspaces-beta/
• https://docs.gitlab.com/ee/user/workspace/

Author Check-list

• Has documentation been updated?