Address review feedback: Resolve N+1 issues
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MR: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/119434+
Address the following potential N+1 problems with `WorkspaceType` and other areas, which were found during review:
- [ ] https://gitlab.com/gitlab-org/gitlab/-/merge_requests/105783#note_1374842474
- _"**Performance:** This will most likely cause an N+1, so we might want to preload it (in the resolver)."_
- https://gitlab.com/gitlab-org/gitlab/-/blob/remote_dev/ee/app/graphql/types/remote_development/workspace_type.rb#L22-22
-
```ruby
field :user, ::Types::UserType,
null: false, description: 'Owner of the workspace.'
```
- [ ] https://gitlab.com/gitlab-org/gitlab/-/merge_requests/105783#note_1374844224
- _"**Performance**: I'm not 100% sure but this also *might* cause an N+1."_
- https://gitlab.com/gitlab-org/gitlab/-/blob/remote_dev/ee/app/graphql/types/remote_development/workspace_type.rb#L14-14
-
```ruby
field :cluster_agent, ::Types::Clusters::AgentType,
null: false,
method: :agent,
description: 'Kubernetes Agent associated with the workspace.'
```
- [ ] https://gitlab.com/gitlab-org/gitlab/-/merge_requests/105783#note_1374939446
- _"**Performance:** We need an N+1 spec in this file"_
- https://gitlab.com/gitlab-org/gitlab/-/blob/remote_dev/ee/spec/requests/api/graphql/remote_development/workspaces_by_ids_spec.rb#L5-5
-
```ruby
RSpec.describe 'Query.workspaces(ids: [RemoteDevelopmentWorkspaceID!])', feature_category: :remote_development do
```
## References
- https://docs.gitlab.com/ee/development/api_graphql_styleguide.html#look-ahead
issue