Fetch and upload FOSS assets cache on FOSS project

What does this MR do and why?

Fetch and upload FOSS assets cache on FOSS project.

This is needed if we want to move all as-if-foss jobs to the FOSS pipeline.

Follow up: !146685 (merged)

Validation

• Manual cache-assets:test for the as-if-foss pipeline: https://gitlab.com/gitlab-org/gitlab-foss/-/jobs/6323004247
  • compile-test-assets cache hit for the FOSS job: https://gitlab.com/gitlab-org/gitlab-foss/-/jobs/6323200296 (project 13083)
  • compile-test-assets as-if-foss cache hit: https://gitlab.com/gitlab-org/gitlab/-/jobs/6323397192 (project 13083)
• Manual cache-assets:production for the as-if-foss pipeline: https://gitlab.com/gitlab-org/gitlab-foss/-/jobs/6323004270
  • compile-production-assets cache hit for the FOSS job: https://gitlab.com/gitlab-org/gitlab-foss/-/jobs/6323324106 (project 13083)
  • compile-production-assets as-if-foss cache hit: https://gitlab.com/gitlab-org/gitlab/-/jobs/6323425828 (project 13083)
• EE on dev: https://dev.gitlab.org/gitlab/gitlab-ee/-/merge_requests/1558
  • compile-test-assets cache hit: https://dev.gitlab.org/gitlab/gitlab-ee/-/jobs/19573210
• FOSS on dev: https://dev.gitlab.org/gitlab/gitlabhq/-/merge_requests/3602
  • compile-test-assets cache miss: https://dev.gitlab.org/gitlab/gitlabhq/-/jobs/19573332
    • Not sure why cache miss for this case? But it's missing a lot of other caches anyway I guess...?

Related to #443498 (closed)