Volunteer feedback-HTML CSS S1-pair for the week not working

**Background**
We got feedback that the exercise '[Pairs for the week](https://github.com/CodeYourFuture/CYF-PD/blob/3f3e884e5bd8f39f86ed8b84847df2fc0ebc1c9a/content/blocks/pairs-for-next-week/readme.md?plain=1#L22)' wasn't successful.
They said:

- It took us a bit to understand what the pairs were for - that there were specific exercises in the week's backlog that trainees needed a pair for.

- [We made this](https://docs.google.com/spreadsheets/d/1uG6OJ6jfGoClS1RMgolN6nNdvyoIoq0H4vGI5XunqvM/edit#gid=0). The 2X2 grid of trainees and times of day couldn't include the days of the week, and each trainee had different availability on different days. This made the spreadsheet redundant, in favour of conversations to find a pair.

**Acceptance criteria**

- [ ] Review the exercise
- [ ] Update the exercise

**Responsible**
- @CodeYourFuture/pd-syllabus-team

**Stakeholders**
- @LaraHuzjan
- @kfklein15

**Aproovers**
- @kfklein15