ci: build docker image for janitor (#1081)

<!--- Provide a general summary of your changes in the Title above -->

## Description

<!--- Describe your changes in detail -->

## Related Issue(s)

- #{issue number}

## Verification

- [ ] **Your** code builds clean without any errors or warnings
- [ ] Manual testing done (required)
- [ ] Relevant automated test added (if you find this hard, leave it and
we'll help out)

## Documentation

- [ ] Documentation is updated (either in `docs`-directory, Altinnpedia
or a separate linked PR in
[altinn-studio-docs.](https://github.com/Altinn/altinn-studio-docs), if
applicable)

.github/workflows/action-publish.yml

@@ -35,6 +35,8 @@ jobs:
             imageName: cdc
           - dockerfile: ./src/Digdir.Domain.Dialogporten.Infrastructure/MigrationBundle.dockerfile
             imageName: migration-bundle
+          - dockerfile: ./src/Digdir.Domain.Dialogporten.Janitor/Dockerfile
+            imageName: janitor
 
     permissions:
       contents: read