Initialize new product analytics stack via GraphQL

What does this MR do and why?

• Adds a new GraphQL mutation: projectInitializeProductAnalytics which attempts to initialize the product analytics tooling for an individual project.
• The job will be attempted 4 times before failing, and allowing the user to trigger the process again.
• We're using a custom way of deduplicating using redis keys rather than :until_executed so that the frontend can know if a job is currently in progress. (I'm open to better ways to achieve this!)

Screencast

See demonstration: https://youtu.be/NCkbsPHWYtg

How to set up and validate locally

1. Enable the feature flag: echo "Feature.enable(:cube_api_proxy)" | rails c.
2. Set up the devkit and start it running using docker-compose up.
3. Visit admin settings and make sure that the settings have been set: /admin/application_settings/general#js-product-analytics-settings
4. As an authenticated user who has developer+ access to a particular project, make the following GraphQL call:

mutation {
  projectInitializeProductAnalytics(input: { projectPath: "flightjs/project_twenty" }) {
    project {
      fullPath
    }
    errors
  }
}

1. Assert that a new background job has been created.
2. Assert that a new connection is created in jitsu.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #383050 (closed)