Fix up Renovate and Dockerfiles (#22) * Turn off major version bumps for Renovate We should always do these manually, in line with * Set up bumping for Rust version to remain consistent * Pin all the actions to specific commits to prevent impersonation attacks * Update Dockerfiles to allow for correct bumping This includes Rust and pinning to the "correct" version of the underlying OSes * Fix up name of Build Step * Move to new style of Renovate Config