tests/router: remove superfluous assertions

[osnyx]

Follow-up of #1312.

According to @ctheune, there is no need to be alerted through an assertion when test harness interface naming logic changes. Other tests implicitly already sufficiently cover wrong interface naming consequences.

@flyingcircusio/release-managers

PL-133497

Release process

• Created changelog entry using ./changelog.sh
  • completely internal follow-up to change that has not been released yet

PR release workflow (internal)

• PR has internal ticket
• internal issue ID (PL-…) part of branch name
• internal issue ID mentioned in PR description text
• ticket is on Platform agile board
• ticket state set to Pull request ready
• if ticket is more urgent than within the next few days, directly contact a member of the Platform team

Design notes

• Provide a feature toggle if the change might need to be adjusted/reverted quickly depending on context. Consider whether the default should be on or off. Example: rate limiting.
• All customer-facing features and (NixOS) options need to be discoverable from documentation. Add or update relevant documentation such that hosted and guided customers can understand it as well.

Security implications

• Security requirements defined? (WHERE)
  • None, removal of a superfluous VM test assertion
• Security requirements tested? (EVIDENCE)

[github-actions]

This PR is ready to merge. Merge scheduled for 2025-03-13