Automate Updates using Renovate

[StevenACoffman]

Hi, this PR automates updating the Dockerfile and versions.env using Renovate. Renovate is a service similar to GitHub Dependabot, but with (fantastically) more configuration options. So many options in fact, if you're new you may want to gloss over [this cheat-sheet](https://www.augmentedmind.de/2021/07/25/renovate-bot-cheat-sheet](https://www.augmentedmind.de/2021/07/25/renovate-bot-cheat-sheet) prior to the official documentation.

This PR adds comments to the Dockerfile file such that a new Renovate Bot configuration with a custom regex will automatically update the Docker file when any new versions of the tools are released in the variety of package managers (go packages, npm packages, debian packages, etc.).

These comment "hints" in the Dockerfile file will help Renovate find the correct packages to update the version information. The renovate.json contains a custom regex manager that will use these hints and update the next line based on the preceding comment's datasource's packageName, and mostly just use the comment's depName as a "displayName" for logging purposes. In addition, there's regular Docker file config that updates the base images.

I also removed the protoc-gen-connect-es as it is not longer necessary with the 2.0 release of the connect framework.

Fixes #9

By the way, I got this technique from https://gitlab.com/kohenkatz/grpc-connect-buf via @kohenkatz