Create example in example repository

[gtrefs]

The readme references an example https://github.com/jlink/jqwik-samples/tree/main/jqwik-testcontainers-gradle which was not yet created.

[jlink]

@gtrefs I added you as collaborator to https://github.com/jlink/jqwik-samples/

[gtrefs]

@jlink thanks. But it seems like a version has to be published to maven first