provide contributor pathways activities in tutorials

following the [learner personas](https://epiverse-trace.github.io/personas/) for this material, complement them with [contributor pathways](https://the-turing-way.netlify.app/project-design/persona/persona-contributors) to each of them about:
- how they would experience their first interaction and
- what pathways they are likely to take to get further involved as contributors

these activities would be distributed per episode as:
- new questions? fill your first issue following `first-good-issue`
- lost in an assessment? As a hint, review our discussion on the topic and get back with complementary info for your solution
- want to extend your capabilities with one package or connect them in a pipeline? check package vignettes or how-to guides!