fix(integration): Several fixes to get tests to pass

[craciunoiuc]

No description provided.

[Copilot]

Pull request overview

This PR adjusts the integration-test harness and CI workflow configuration to address recent failures and improve compatibility across different test servers/environments.

Changes:

• Centralizes test-server selection logic via a new GetTestServer helper and updates server-based skipping accordingly.
• Updates instance integration tests to match current instance inspect output and adds a propagation delay intended for prod nodes.
• Tweaks the GitHub Actions integration-test configuration generation (including enabling insecure and switching UNIKRAFT_ORG sourcing).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
internal/integration/skip.go	Uses the new helper to decide when to skip tests on unsupported servers.
internal/integration/config.go	Adds GetTestServer helper for test-server support detection.
cmd/unikraft/integration/instance_test.go	Updates output assertions and adds a prod-propagation delay.
.github/workflows/test.yaml	Updates generated config for integration tests and CI env wiring.

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[jedevc]

Tests still failing 🤔