Add Helm and Kubectl

[iptizer]

I know there is a [dedicated lambda layer for kubectl and helm]{https://github.com/aws-samples/aws-lambda-layer-kubectl}, nevertheless, this repository is more mature and has a lot of other tools already included. That is why I would appreciate addin helm & kubectl binaries here.

I would be happy to assist, I could provide the hashed of the binaries, which may be verified. So I don't see any security risks here.