Remove Docker release process

This is not a fix but temporarily unblocks us from being able to publish kubeaudit package releases.

[ ] I have :tophat: my changes (A 🎩 specifically includes pulling down changes, setting them up, and manually testing the changed features and potential side effects to make sure nothing is broken)
[ ] I have performed a self-review of my own code
[ ] I have made corresponding changes to the documentation
[ ] I have added tests that prove my fix is effective or that my feature works
[ ] New and existing unit tests pass locally with my changes
[ ] The test coverage did not decrease
[ ] I have signed the appropriate Contributor License Agreement

Shopify / kubeaudit