Starter Kit: CI/CD with Github Actions

### Background on the problem the feature will solve/improved user experience
Manual cloud deployments are tedious.

### Describe the solution you'd like
Once we've validated our manual deployments we would like to have CI/CD to deploy easily to cloud across all Open Sentencing repositories.

### Tasks

Add github actions for:
- [ ] building
- [ ] unit testing
- [ ] accessibility testing
- [ ] linting
- [ ] deployment

Related Issues:
- https://github.com/Call-for-Code-for-Racial-Justice/Open-Sentencing-Aggregator/issues/30
- https://github.com/Call-for-Code-for-Racial-Justice/Open-Sentencing-Aggregator/pull/20
- https://github.com/Call-for-Code-for-Racial-Justice/Open-Sentencing/issues/28
- https://github.com/Call-for-Code-for-Racial-Justice/Open-Sentencing-Aggregator/issues/28
- https://github.com/Call-for-Code-for-Racial-Justice/Open-Sentencing-UI/issues/63

### Acceptance Criteria

Inizia esaminando le issue e la pull request correlate, in particolare Aggregator issue 30 e PR 20, per comprendere il processo manuale di deployment esistente tra i repository. L’issue non indica file, test, provider cloud o criteri di accettazione; il completamento dovrebbe coprire workflow per la build, gli unit test, i test di accessibilità, il linting e il deployment.

Scritto dal modello di indicizzazione a partire dal testo della issue.