Follow-up from "Log all GC stats when measurements are enabled"

The following discussion from !25603 (closed) should be addressed:

• @nmilojevic1 started a discussion: (+4 comments)

  I started working on !25598 (merged). I extracted measuring to the separate library measurable.rb, so we could use it on various places, like import.rake or export.rake.

  https://gitlab.com/gitlab-org/gitlab/-/blob/54972720644ab85158a6ead67d5791abfaba9f68/lib/gitlab/measurable.rb

  Also we could introduce different loggers. So I am wondering, how to approach this/merge these two?

  I also added those two:

  logger.info "Memory usage: #{Gitlab::Metrics::System.memory_usage.to_f / 1024 / 1024} MiB"
  logger.info "Label: #{::Prometheus::PidProvider.worker_id}"

  I like the idea, I don't see why we shouldn't log all gc stats. Excellent.

In !25603 (closed) we extended on the amount and format of data we collect during ~import. However, that work collided with other ongoing issues, so we closed that MR.

Let's bring back this functionality by applying it to what is now on master.