Support Using nodeSelector to Select Nodes for New Workspaces
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### Proposal
In the agent configuration file located at `/.gitlab/agents/<agent-name>/config.yaml`, it would nice to be able to add an additional parameter with a structure like this:
```
remote_development:
enabled: true
gitlab_workspaces:
nodeSelector: gitlab-ws-nodes
```
We would then use this value in the Workspaces deployments, as outlined here:
https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#nodeselector
With this approach, we can manage a separate node pool for Workspaces based on the `nodeSelector`. For example, we could assign t3 nodes for developers and c7 nodes for EKS runners.
This setup would also allow us to deploy different agents that use different nodes — one for development and another for executing more resource-intensive tasks such as tests or analysis.
issue