Create pipeline/s to run AI E2E tests which use a real AI provider

From: https://gitlab.com/gitlab-com/gitlab-OKRs/-/work_items/5920#note_1852163767

general

• Verify environment is up and running
• Ensure smoke tests (non-AI) pass https://gitlab.com/gitlab-org/quality/gitlab-qa-executor/-/pipelines/1248588495 - [ ] Identify/create user which has access to AI services N/A

gitlab tests

• Add tags to gitlab tests identifying e2e tests that invoke the external ai provider gitlab-org/gitlab!149032 (merged)
• Verify manually that Code Suggestions works in environment under test
• Verify manually that Duo Chat works in environment under test
• Modify/clone https://gitlab.com/gitlab-org/quality/gitlab-qa-executor (additional env variables may need to be added) - [ ] Configure https://gitlab.com/gitlab-org/quality/gitlab-qa-executor with ai user N/A
• Run AI tests -> Passing run ✅ https://gitlab.com/gitlab-org/quality/gitlab-qa-executor/-/jobs/6644577268#L349
• Document instructions -> #2578 (comment 1875938656)

ide tests (vscode and jetbrains)

• Verify manually that the extension works when configured to use environment under test
• Add additional pipeline schedule for new environment using AI token from the environment
• Run tests (ad hoc?/schedule?) (if test is to be run many times/long term, we may have to consider running it outside of the project as it will occur costs for the project)