clarify the 'GitHub Issues and Pull Requests Course' section (fixes #3525)

[MelonLord8]

Important: Do not tick a checkbox if you haven’t performed its action.

Before Creating the Pull Request

• Verify the changes are on a new branch other than master – it should say "compare: branch-name".
• Start the pull request title with lowercase letters, e.g., add githubusername.md.
• Add issue number to the end of the pull request title when applicable, e.g., update mi-faq.md (fixes #3264).

After Creating the Pull Request

• Go to "Commits" tab, make sure the commit username is clickable and linked to your GitHub account correctly.
• Review the "Files changed" tab to ensure there are no unnecessary files or changes included in the pull request.
• Verify that the raw.githack preview link is included in the description.
  • Preview the MDwiki rendered changes using the raw.githack link. Ensure it displays as expected without any errors.
• Drop a link to this pull request in our discord channel.

Description, Screenshots and/or Screencast

Reformatted the "GitHub Issues and Pull Requests" Course section in step 7 of the mi onboarding from the long bullet points to divided and smaller lines which should make it easier to digest.

Before:

After:

fixes #3525

Raw.Githack Preview Link

https://raw.githack.com/MelonLord8/MelonLord8.github.io/3525-clarifying-step-7-mi/index.html#!./pages/mi/mi-myplanet-course.md