01-git lecture adjustments

[tm-pham]

• Include slide on Git initialization using Github CLI and///or Github Desktop
• Include slide on Git initialization on CHPC
• Include slides on Git under the hood (but will only discuss if we have enough time)
  • What git init actually creates (the .git/ folder structure)
  • How Git stores data as objects: blobs, trees, and commits
  • SHA-1 content hashing and how Git keeps track of file changes and commits