test: remove obsolete sniff tests

[ricellis]

PR summary

Remove obsolete sniff tests

Fixes: part of s669

PR Checklist

Please make sure that your PR fulfills the following requirements:

• The commit message follows the
  Angular Commit Message Guidelines.
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• New tests
• Build/CI related changes
• Documentation content changes
• Other (please describe) - remove obsolete tests now covered elsewhere

What is the current behavior?

Sniff tests duplicate testing covered elsewhere.

What is the new behavior?

Remove sniff tests.

Does this PR introduce a breaking change?

• Yes
• No

Other information