Update instructions to allow for PR based review

[LonMcGregor]

• Changes the workflow from Template to Fork, allowing for PR review.
• Needs an extra step of trainees adding their partner as a collaborator to their repo.
• Updated review instructions with criteria.

• Adds summary of requirements for reviewers
• Adds updated review steps in the readme and levels
• Update the primary backlog task ticket (submission section and labels) - TV Show Project Module-Data-Flows#44
• Update the relevant backlog tickets
  • copy levels/level-0.md to TV Show Project Level 0: Set up project Module-Data-Flows#474
  • copy levels/level-100.md to TV Show Project Level 100: Display information about every episode of a single TV show. Module-Data-Flows#475
  • copy levels/level-200.md to TV Show Project Level 200: Swap Codebases Module-Data-Flows#476
  • copy levels/level-300.md to TV Show Project Level 300: Swap back to your old codebase Module-Data-Flows#477
  • copy levels/level-400.md to TV Show Project Level 400: Fetch much more data Module-Data-Flows#478
  • copy levels/level-500.md to TV Show Project Level 500: Build a front page Module-Data-Flows#479
  • copy levels/level-999.md to TV Show Project Level 999: Stretch Module-Data-Flows#480
• Update the repository template issues templates to allow for reviewing projects
• Communicate with reviewers to ensure they know how to find projects awaiting review / how to review this one
• update trainee tracker to track this
• update itp reviews waiting page to track this - CodeYourFuture/curriculum@039c8d2
• optional - Update link deployed after reach level 500 for TV-Show curriculum#1845 and that guidance is updated to use github pages

[Poonam-raj]

Looks fab, bunch of qs and suggestions so take that you need