feat: Add OCI standard labels to Dockerfile (#3412)

<!-- Thank you for making a PR! Bug fixes are always welcome, but if
you're adding a new feature or changing an existing one, we'd really
appreciate if you open an issue, post on the forum, or drop in on
Discord -->

## Checks
- [x] I am happy for maintainers to push small adjustments to this PR,
to speed up the review cycle
- [x] I have checked that there are no existing pull requests for the
same thing

Hi there! Just a small thing I noticed; I self-host an Atuin server via
Docker and have started bumping my compose dependencies with Renovate.
They have a feature that pulls the changelog and displays it in-line in
the PR, which is handy when it works! - but currently this doesn't work
for Atuin. According to [their
documentation](https://docs.renovatebot.com/modules/datasource/docker/#description),
the `org.opencontainers.image.source` label needs to point to the
repository for them to grab release notes. Renovate cites their
Dockerfile as an example, so I took a look at [the actual
Dockerfile](https://github.com/renovatebot/renovate/blob/main/tools/docker/Dockerfile)
to see if they had any other labels, and figured I'd pop those in as
well.

No particularly strong feelings on the labeling itself, styling, etc; so
free free to make any changes deemed necessary :)

0 files changed, 0 insertions, 0 deletions