1. Add Ruby 2.7 specific Gemfile that uses an older version of nokogiri
2. Rails edge doesn't support Ruby 2.7.0, so exclude it.
3. Add Ruby 3.3
4. Update Gemfile.lock to test against Rails 7.1.2 as it's the latest
version.
5. Remove continue-on-error from the matrix and always set to true
The workflow was failing with:
```
The workflow is not valid. .github/workflows/docker-publish.yml (Line: 22, Col: 14): Unexpected symbol: '|'. Located at position 12 within expression: github.ref | replace('refs/tags/', '')
```
The `set-output` command is deprecated, so the issue has been fixed by utilising the `github.ref_name` context to retrieve the version tag that triggered the workflow.
> `github.ref_name`: The short ref name of the branch or tag that triggered the workflow run. This value matches the branch or tag name shown on GitHub. For example, `feature-branch-1`.
https://docs.github.com/en/actions/learn-github-actions/contexts
