Fixes to chain strategy example in outlier_reduction.md

[reuning]

What does this PR do?

The chain strategies example in the outlier reduction has new_topics being acted on in the first step and then topics acted on in the second step. I'm pretty sure this is supposed to be other way around. This fixes that.

Before submitting

• [X] This PR fixes a typo or improves the docs (if yes, ignore all other checks!).
• [ ] Did you read the contributor guideline?
• [ ] Was this discussed/approved via a Github issue? Please add a link to it if that's the case.
• [ ] Did you make sure to update the documentation with your changes (if applicable)?
• [ ] Did you write any new necessary tests?

[MaartenGr]

Yep, you are completely right! Thank you for the PR 😄