Check for automountServiceAccountToken

[MrKrabat]

Is your feature request related to a problem? Please describe.
Kubernetes automatically mounts serviceaccount tokens into running pods. You can use this token to authenticate to the Kubernetes API. It is considered good practice to disable this behavior. 99% of all applications will not use this token anyway.

Describe the solution you'd like
Kubesec should include a check for automountServiceAccountToken and recommend setting it to false.