Does this test as it stands clean up the changes to `Thread.current['request-id']`? Its dangerous for the the test to be modifying persistent state - later tests could be affected in unexpected ways.

Also, calling `subject` explicitly like that is obfuscating what the test actually does. I think the intention of `subject` in rspec is more about one line `its(:thing) { should eq 'some expected value' }` style assertions, and shared examples.