Test gRPC DEV UI messaging

[michalvavrik]

The gRPC DEV UI allows to test gRPC client - send a message from DEV UI to gRPC server and receive answer. We have done it with the old DEV UI, but to do same with a new DEV UI would be very fragile. There are no hooks for selectors and with the Playwright it's harder to navigate in shadow roots. First, we need to change Quarkus main project and add there id's or classes that we can use as selectors during testing and then, we can start testing it again.

See:

• https://github.com/quarkus-qe/quarkus-test-suite/blob/main/http/http-advanced/src/test/java/io/quarkus/ts/http/advanced/DevModeGrpcIntegrationIT.java
• https://github.com/quarkus-qe/quarkus-test-suite/blob/main/http/http-advanced-reactive/src/test/java/io/quarkus/ts/http/advanced/reactive/DevModeGrpcIntegrationReactiveIT.java