Remove kubectl gavinbunny Provider and switch to native

[nce]

Because @jmederer and others frown upon the usage of the gavinbunney/kubectl Provider, we'll switch to native hcl.

All kubectl_manifest resources should be replaced, with e.g. with this tool: https://github.com/sl1pm4t/k2tf which should do most the lifting.

[tim-tschiersch]

new detailed issue has been opened -> https://github.com/adorsys/ops-k8s-bootstrap/issues/43