Add Helm chart for easy deployment

[Luzifer]

As a Kubernetes operator I want to be able to create an OTS instance easily without having to write the chart myself. The repo should bring its own chart.

To ease deployment on K8s create a chart containing options for customization.

[hypery2k]

I've created a chart: https://github.com/ContinuousSecurityTooling/ots-helm-chart

Feel free to link it, if you like. Currently it's very basic, but for the beginning it works. Will automatically synced with newer releases via renovate

Chart Values are described here: https://github.com/ContinuousSecurityTooling/ots-helm-chart/tree/develop/chart#values