Fixes https://github.com/quarkusio/quarkus/issues/35605
~~Needs a branch from smallrye grapgql https://github.com/smallrye/smallrye-graphql/pull/2287~~

Some questions:

1. Is there really no context handling needed? As stated here:io.quarkus.virtual.threads.ContextPreservingExecutorService
2. ~_{How to prevent the virtual thread executor from being removed?}~

Probably we will need more tests, but at least io.quarkus.virtual.graphql.RunOnVirtualThreadTest#testAnnotatedBlockingObject tests for virtual thread and works.