Jovatn/test spec minor fixes

[jovatn]

Description

Minor fixes to test descriptions and test steps, typically spelling errors, missing words, incorrect IP addresses, etc.

Other information

Checklist

Tick relevant boxes, this PR is-a or has-a:

• [ ] Bugfix
  • [ ] Regression tests
  • [ ] ChangeLog updates (for next release)
• [ ] Feature
  • [ ] YANG model change => revision updated?
  • [ ] Regression tests added?
  • [ ] ChangeLog updates (for next release)
  • [ ] Documentation added?
• [ ] Code style update (formatting, renaming)
• [ ] Refactoring (please detail in commit messages)
• [ ] Build related changes
• [X] Documentation content changes
• [X] Other (please describe): Updates test documentation

[axkar]

Excellent job reviewing this thoroughly! I've added a few minor comments, but feel free to treat them as optional :)