Update numerous dependencies

[eric239]

I have a fork of this repo (basically just slapping a Dockerfile on top). In my fork, default security vulnerabilities checks are enabled and there are a few critical ones and a bunch of others, due to numerous dependencies being out of date.

Does this repo still have a maintainer? It would be nice if they bumped all (at least security impacting) deps to their latest (or safe) versions. Some of the auto-generated dependabot PRs in my fork actually break tests so at least some of the upgrades require expertise in the codebase. I'm not a golang developer and thus don't feel like I can do justice to this task myself.