feat(testkube): add networkpolicy support

[windowsrefund]

Pull request description

Adds Network Policies support

Checklist (choose whats happened)

• [ ] breaking change! (describe)
• [x] tested locally
• [x] tested on cluster
• [ ] added new dependencies
• [ ] updated the docs
• [ ] added a test

Breaking changes

• none

Changes

• none

Fixes

• none

Additional Info

This will be useful to those folks who use network policies with a default-deny configuration. Only Testkube-specific traffic has been accommodated for and by default, these resources will not be created (must enable in values.yaml). I came up with these rules by watching for PacketDrop events (provided by kube-iptables-tailor) in the testkube namespace while running my Test Suites, etc. Hopefully, I didn't miss anything! Also, I am still on 1.16.64 so I added support for the dashboard if enabled.

I didn't update the README as I came to believe it may be auto-generated. LMK if I'm wrong and I'll be happy to update accordingly.

To see the template rendered:

cat << EOF > /tmp/values.yaml
networkPolicy:
  enabled: true
EOF

Now from inside the testkube chart directory

helm template testkube . -f values.yaml -f /tmp/values.yaml -s templates/networkpolicy.yaml