Feedback section - exercise edit

### How could the content be improved?

In my training today, I edited the "Using Feedback" exercise in the Feedback section.
Currently, it focuses on how you can use the feedback from others when the previous exercise has them focusing more on practicing the giving feedback aspect. This may be intentional (so they look at both sides) but given my emphasis on not being concerned about making mistakes (as that would provide opportunities for their group members to give feedback), I didn't feel like they should be too focused on using those particular pieces of feedback and thought I'd save that for the other teaching practice exercises.
Instead I had them do a reflection exercise on the process of giving and receiving feedback. "How did it feel to give feedback to the others? What did you learn from the experience? Did you learn anything from receiving feedback from your group members?"
Thinking on it, I'm wondering if maybe that should be the focus of their efforts all together, rather than even recording notes on their feedback from the previous exercise actually. So combining them and having them reflect instead of writing down the feedback they received. If this change is supported, I'm happy to file a PR on it.

### Which part of the content does your suggestion apply to?

https://carpentries.github.io/instructor-training/instructor/11-practice-teaching.html

Read the Feedback section in instructor/11-practice-teaching.html and compare the current "Using Feedback" exercise with the preceding exercise. Confirm the intended focus with maintainers, then update the exercise so its instructions and reflection prompts match the agreed approach; the linked lesson should clearly show the final content.

Written by the indexing model from the issue text.