RuboCop: Fix RSpec/ExpectChange offenses for spec/{worker,support}

What does this MR do and why?

This MR fixes RSpec/ExpectChange offenses for spec/support and spec/workers. It also remove these files from the TODO list.

Done via:

bundle exec rubocop -A --only RSpec/ExpectChange spec/workers spec/support

Contributes to #239356.

How to set up and validate locally

bundle exec rubocop --only RSpec/ExpectChange spec/workers spec/support

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.