Add helm chart documentation for workspaces
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## Summary
Add documentation for enabling workspaces through GitLab Chart.
Related : https://gitlab.com/gitlab-org/charts/gitlab/-/issues/6186#note_2853995465
## Steps to reproduce
N.A.
## Configuration used
N.A.
## Current behavior
Docs for enabling/configuring workspaces is missing.
## Expected behavior
Docs for enabling/configuring workspaces must be available.
## Versions
- Chart: (tagged version | branch | hash `git rev-parse HEAD`)
- Platform:
- Cloud: (GKE | AKS | EKS | ?)
- Self-hosted: (OpenShift | Minikube | Rancher RKE | ?)
- Kubernetes: (`kubectl version`)
- Client:
- Server:
- Helm: (`helm version`)
- Client:
- Server:
## Relevant logs
(Please provide any relevant log snippets you have collected, using code blocks (```) to format)
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