Pull CYF-PD blocks into this repo

[illicitonion]

There are currently a bunch of blocks being pulled in from a CMS we put together in the hopes that less technical contributors would find it easier to contribute via a CMS. These are all blocks whose src starts https://cyf-pd.netlify.app

This adds complexity we don't need. No one is actually using that CMS, so this just adds Yet Another way things are done, and makes updates harder to test and review.

We should pull these blocks into this repo, and just use them as standard markdown blocks.

There are a bunch of these in tracks but we can ignore these for now. The important ones we need to migrate, because people actually want to improve the content, are all in org-cyf-itp:

% rg cyf-pd org-cyf-itp
org-cyf-itp/content/data-groups/sprints/2/prep/index.md
37:src="https://cyf-pd.netlify.app/blocks/prep-conflict-resolution/readme/"

org-cyf-itp/content/data-flows/sprints/3/day-plan/index.md
15:src="https://cyf-pd.netlify.app/blocks/teamwork-project-s3"

org-cyf-itp/content/data-flows/sprints/1/day-plan/index.md
15:src="https://cyf-pd.netlify.app/blocks/teamwork-project-s1/readme/"

org-cyf-itp/content/data-flows/sprints/2/day-plan/index.md
15:src="https://cyf-pd.netlify.app/blocks/teamwork-project-s2"

org-cyf-itp/content/data-groups/sprints/1/prep/index.md
50:src="https://cyf-pd.netlify.app/blocks/fail-fast-prep/readme/"

org-cyf-itp/content/structuring-data/sprints/1/day-plan/index.md
22:src="https://cyf-pd.netlify.app/blocks/asking-good-technical-questions"

On the plus side, that's only 6 things to migrate!

To migrate one:

1. Get the ITP site running locally - see https://github.com/CodeYourFuture/curriculum/blob/main/CONTRIBUTING.md#developing-the-source-website for tips here (though we want to improve this documentation! The biggest thing to look out for is you need a specific version of hugo)
2. Find the linked block in https://github.com/CodeYourFuture/CYF-PD/tree/main/content/blocks - migrate its markdown into a directory in https://github.com/CodeYourFuture/curriculum/tree/main/common-content/en/blocks (https://github.com/CodeYourFuture/curriculum/blob/main/common-content/en/blocks/cv-personal-statement-matching/index.md?plain=1 is a good example to copy from)
3. Update the src= link in the day plan from the cyf-pd link to just the directory name the file was migrated to (e.g. blocks/cv-personal-statement-matching for the above example)

If we want to replicate the tab-like structure of the PD curriculum blocks, we probably want to use https://common.codeyourfuture.io/common-theme/shortcodes/tabs/ - but we shouldn't just do this because the PD content used them - it's ok for us not to use tabs if that makes more sense.

I'd recommend doing one of these