Fix prometheus client pid reuse bug

Updates prometheus client, to version that correctly handles PID being changed when new worker is forked.

Additionally, new functionality has been introduced to allow safer pid switching, where every PID dependant object is reinitialized.

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• 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?

Related #35588 (closed)