Automate Spectral Ruleset releases with calculated SemVer and release notes

- [ ] Update release workflows to determine next version based on [Conventional Commits](https://www.conventionalcommits.org/en/v1.0.0/), including generation of release notes


See parent task #19 for additional details.

#### Useful links

[Release Please](https://github.com/googleapis/release-please)
[semantic-release](https://github.com/semantic-release/semantic-release)