Draft: Write first draft of episode 3 - demo project

• Change and refine the structure of the episode.
• Add content to the episode:
  • Summary of things to learn
  • Introduction
  • Demo project
  • Use Cases
  • CI pipeline development
  • Wrapping up with things learned

Closes #4 (closed)

added Progress::3_Doing label

assigned to @hueser93

added Progress::0_Stale label and removed Progress::3_Doing label

closed