Add trigger_job_retry_action feature flag

What does this MR do and why?

We already have the ci_retry_downstream_pipeline feature flag that determines if the trigger job links in the mini pipeline graph will lead to the downstream pipeline page or the new trigger job page.

Since we're releasing the trigger job page without the retry actions, we need to hide the retry button first before enabling the feature flag. Since the trigger page is a whole new vue app on the frontend, I would still like to proceed with rolling out a separate feature flag for the trigger job page rather than move the flag to just hide the retry button. The retry functionality is tied to the button so we shouldn't need to revert the whole page for it if we need to disable the retry functionality.

Screenshots or screen recordings

Feature Flag	Result When Clicking on Trigger Job Link
All FF disabled
trigger_job_retry_action disabled; ci_retry_downstream_pipeline enabled
trigger_job_retry_action enabled; ci_retry_downstream_pipeline disabled
All FF enabled

How to set up and validate locally

1. Add the following content to your .gitlab-ci.yml file:

   stages:
     - prepare
     - deploy
   
   job:
     stage: prepare
     script:
       - echo "running prepare_job"
   
   triggerJob:
     stage: deploy
     trigger:
       include:
         - project: "/path/to/project" # replace with another project
           file: ".gitlab-ci.yml"

2. Visit the pipeline and click on the triggerJob job pill.
3. If trigger_job_page FF is enabled, it should redirect to the trigger job page.
   • If ci_retry_downstream_pipeline is further enabled, the retry button should be visible.

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.