Add workshop and update day plan for JS2 Week 2

[Dedekind561]

Acceptance criteria

• Workshop for JS2 Week 2 is added to the CYF-Workshops repo
• day plan for JS2 Week 2 is updated linking to the new workshop
• Workshop content is aligned to the prep content for the week

[SallyMcGrath]

All these tasks are checked. What is still to be done, @Dedekind561 ?