Add sample preStart events to remote development fixtures
MR: Pending
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## Description
This is a follow up to this discussion here: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/192698#note_2549427682
We would like to add some preStart events to our remote development fixture files for completeness since we already include postStart events.
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## Acceptance criteria
- [ ] Add preStart event to `ee/spec/fixtures/remote_development/example.devfile.yaml.erb`
- [ ] Add preStart event to other fixtures where needed
- [ ] Update the `workspace_deployment` method in `remote_development_shared_contexts.rb` to return the expected configuration including the preStart event we added to the fixture
- [ ] Make sure the smoke-test-suite passes
## Implementation plan
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[Provide a high-level plan for implementation of this issue, including relevant technical and/or design details.]
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