Add Job Created subscription

What does this MR do and why?

The purpose of this MR is to implement a subscription for the jobs list view Frontend to update the list as soon as

• ciJobCreated requires a global Project ID to initiate the subscription.
• the subscription is triggered when a job is created using the after_commit hook on create
• the subscription payload is a Ci::JobType

References

• [FF] `ci_job_created_subscription` -- Real time... (#562507)

Screenshots or screen recordings

How to set up and validate locally

1. Enable FF ci_job_created_subscription
2. Visit http://gdk.test:3000/-/graphql-explorer and use the subscription with your project ID

subscription {
  ciJobCreated(projectId: "gid://gitlab/Project/36") {
    id
    status
    startedAt
  }
}

4. Create a new pipeline and watch data update in the explorer and network tab (sockets)

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.