Use GlAvatar in environments dashboard

What does this MR do and why?

Replace user_link_avatar with GlAvatar in the Environments dashboard for environment folders.

#355869 (closed)

Screenshots or screen recordings

before	after

How to set up and validate locally

1. Set up a local gitlab runner with GDK: https://gitlab.com/gitlab-org/gitlab-development-kit/blob/main/doc/howto/runner.md
2. On a GitLab project, create 2 environments with the following names: (on :project/-/environments):
   1. myfolder/prod
   2. myfolder/staging
3. On a GitLab project, add the following gitlab-ci.yml file to mock a deployment:

deploy_prod:
  stage: deploy
  script:
    - echo "Deploy to prod-test server"
  environment:
    name: myfolder/prod
    url: https://google.com

1. Trigger a deployment by creating an MR and merging it.

2. Navigate to the folder's dashboard:

   

3. Observe the list of deployments, and the glavatars

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.