Nuke Docker support

Our Docker infrastructure is a pain in the ass to maintain, because of
all the flakiness surrounding it. Remove it from the code base.

Author: d-e-s-o

.github/workflows/docker.yml

@@ -1,6 +1,6 @@
 Unreleased
 ----------
-- Updated base image version used in Docker image
+- Removed `Dockerfile` and Docker image build CI job
 - Bumped `git2` dependency to `0.20`
 
 

CHANGELOG.md

@@ -107,36 +107,6 @@ setting, such as on a single computer or local home network. The reason
 being that, by design, it does not have any authentication scheme
 present and no attempts of hardening the code have been undertaken.
 
-Docker
-------
-
-To run the registry in a Docker container:
-
-```sh
-docker run -p 35504:35504 ghcr.io/d-e-s-o/cargo-http-registry:latest /tmp/test-registry --addr 0.0.0.0:35504
-```
-
-To run `cargo-http-registry` in a docker compose file:
-
-```yaml
-version: "3"
-
-services:
-  registry:
-    image: ghcr.io/d-e-s-o/cargo-http-registry:latest
-    container_name: cargo-registry
-    restart: always
-    # Arguments:
-    # - Directory where the registry will store its data.
-    #   Cargo-http-registry creates the directory if it does not exist.
-    # - Server address.
-    #   Note that 127.0.0.1 doesn't work in GitHub actions.
-    #   Use 0.0.0.0 instead.
-    command: /tmp/test-registry --addr 0.0.0.0:35504
-    ports:
-      - "35504:35504"
-```
-
 [cargo-config]: https://doc.rust-lang.org/cargo/reference/config.html
 [cargo-net-git-cli]: https://doc.rust-lang.org/cargo/reference/config.html#netgit-fetch-with-cli
 [docs-rs]: https://docs.rs/crate/cargo-http-registry