feat: add UI Unit test base class for Quarkus

[mcollovati]

Description

Adds a base class for UI Unit testing on Quarkus. Provides mocks for QuarkusVaadinServlet and QuarkusVaadinServletService integrated with Quarkus CDI.

Fixes vaadin/quarkus#140 Part of #1655

Type of change

• [ ] Bugfix
• [x] Feature

Checklist

• [x] I have read the contribution guide: https://vaadin.com/docs/latest/guide/contributing/overview/
• [x] I have added a description following the guideline.
• [x] The issue is created in the corresponding repository and I have referenced it.
• [x] I have added tests to ensure my change is effective and works as intended.
• [ ] New and existing tests are passing locally with my change.
• [ ] I have performed self-review and corrected misspellings.

Additional for Feature type of change

• [ ] Enhancement / new feature was discussed in a corresponding GitHub issue and Acceptance Criteria were created.