fix(tracing): activate distributed headers in the rq integration

[juzna]

This was forgotten in 9a5fd14.

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[juzna]

Hi, I'm completely new to this repo, so sorry if the contribution is not done correctly.

I noticed that in the rq integration, trace id is not propagated between services. One line was missed in the linked commit, so just adding it here.

Tested by applying the same change locally in our worker repo, and confirmed that it fixes the issue.