3.3 - Update nf-core training to use topics for version channel

Content updates

• Hello nf-core (#896):
  • Updated course and rebuilt all solution files (Parts 2-5) for nf-core tools 3.5.2.
  • Added version capture section with topic channels to Part 4.
  • Removed shebangs from module file code snippets and fixed hl_lines in Part 4.
  • Fixed assorted typos and inconsistencies across Parts 2-4 docs.

Full Changelog: 3.2...3.3