Add a toolchain for template "Deploy a Kubernetes App with Helm"

Implement Lab2, Create a Toolchain - Deploy a Kubernetes App with Helm,
See https://github.com/open-toolchain/simple-helm-toolchain

Go to https://cloud.ibm.com/devops/create?env_id=ibm:yp:us-east
You will see an option to use the `simple-helm-toolchain` template,

For an example also see the Lab1 `Deploy a Kubernetes App` toolchain