Hackathon experience improvement: add custom role to Discord for each hacakthon

[jlengstorf]

Let's create a custom role for anyone who completes a hackathon. This role would use the same icon as #41 and would theoretically be possible to hook up into the same automation that adds the badge.

• Create roles per hackathon
• Add role ID to the Sanity type created in Hackathon experience improvement: add custom badges to CodeTV profiles for participants #41
• Add workflow to assign the role to the user