improve: use binaries from GitHub releases in Kube API Tests

[csviri]

Description

Fix #6277

Uses new approach approach of storing binaries in GitHub for KubeAPITest. Envtest changed its approach, see: kubernetes-sigs/controller-runtime#2811
So, we must also migrate since the former storage approach will be removed.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• Feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change
• Chore (non-breaking change which doesn't affect codebase;
  test, version modification, documentation, etc.)

Checklist

• Code contributed by me aligns with current project license: Apache 2.0
• I Added CHANGELOG entry regarding this change
• I have implemented unit tests to cover my changes
• I have added/updated the javadocs and other documentation accordingly
• No new bugs, code smells, etc. in SonarCloud report
• I tested my code in Kubernetes (does not apply)
• I tested my code in OpenShift (does not apply)

[csviri]

closes #6277

[sonarqubecloud]

Quality Gate failed

Failed conditions
1 Security Hotspot

See analysis details on SonarCloud

[manusa]

LGTM, thx!