Remove QA Tunnel docs

What does this Merge Request do?

The QA tunnel is no longer available, so we are removing the tunnel services and the auto_devops setting that controlled it (!1715 (merged)). This merge request removes the documentation for these settings, and moves anything not directly related into a more generic kubenetes/ directory.

#1122 (closed)

Merge Request checklist

• [-] Tests added for new functionality. If not, please raise Issue to follow-up.
• [-] This change is backward compatible. If not, please include steps to communicate to our users.
• Documentation added/updated, if needed.
• [-] gdk doctor test added, if needed.