Introduce check-metricsscraper-singlenode

[twz123]

Description

This is a variant of check-metricsscraper that executes the inttest on a single-node cluster. This mainly means that, in addition to etcd, kine scraping is also tested. Use the JSON API and look for the push_time_seconds metric. Collect all job labels that had successful pushes and compare it to the list of expected jobs.

See:

• kube-router failed to start when installation with default settings #4411
• Change kine metrics port from 8080 to 2380 #4421

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

How Has This Been Tested?

• Manual test
• Auto test added

Checklist:

• My code follows the style guidelines of this project
• My commit messages are signed-off
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

[k0s-bot]

Successfully created backport PR for release-1.30:

• [Backport release-1.30] Introduce check-metricsscraper-singlenode #4439