Creates CI Header component to use in pipelines and job details pages

What does this MR do?

Creates a reusable shared component between pipeline's details page and job's detail page.

The original MR is https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/11340, this is just a port in order to merge it into master directly.

Why was this MR needed?

The goal is to make both pipeline's details page and job's detail page realtime. This header is shared between them.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

#31397 (closed)

@iamphill can you please review this one? You already reviewed it the first time 😊

Looks pretty simple 👍 Just some small comments 😄

resolved all discussions

@iamphill done 👍 Also changed the mixing to have methods like it had in the 1st MR, makes it easier to use :)

Can you please review again? Thanks!

assigned to @iamphill

Ups, forgot to update the tests 🤦

assigned to @filipa

@iamphill can you please review again? Thanks!

assigned to @iamphill

Just the one thing 👍 Sorry I didn't notice it before!

resolved all discussions

@iamphill no need to be sorry! Nice catch! :)

Fixed 💪 Can you review again? Thanks!

approved this merge request

@filipa Thanks! 😄 enabled MWPS 👍

merged

mentioned in commit 7911f1c0

mentioned in issue #36072 (closed)