Introduce sanity e2e tests for KubeRay

[mimowo]

What would you like to be added:

Sanity e2e tests for KubeRay (RayJob and RayCluster). In particular the submitted Job mode as in #3729

Why is this needed:

To ensure the basic integration with KubeRay works. We can cover corner cases in integration and unit tests.

[mimowo]

cc @andrewsykim @mbobrovskyi @tenzen-y

/assign @kaisoz
tentatively, who might want to take it as an automated follow up to #1568 (though it is a bit different because testing the issue fully requires manageJobsWithoutQueueName, and so it also requires #3767)