Publish JAR for re-use

[ajtucker]

As a third-party user of this library, I would like to add csv-check as a dependency as I would with other open source libraries, e.g.

<dependency>
    <groupId>io.github.gss-cogs</groupId>
    <artifactId>csvw-check</artifactId>
    <version>0.0.3</version>
</dependency>

The built jar could be published to GitHub's Apache Maven registry.

• Ensure copyright is asserted.
• Update GitHub action to publish via sbt publish.