Fix getAnyPod throwing IllegalArgumentException when no pod found

[vsalbaba]

Fix getAnyPod throwing IllegalArgumentException when no pod with specified labels is found.

Now it throws an explained RuntimeException.

Please make sure your PR meets the following requirements:

• [x] Pull Request contains a description of the changes
• [x] Pull Request does not include fixes for multiple issues/topics
• [x] Code is formatted, imports ordered, code compiles and tests are passing
• [x] Code is self-descriptive and/or documented

[mnovak1]

@vsalbaba do you have any CI run with EAP OCP TS to make sure it does not break anyhting?

Edit: Could you create an issue as well, please?

[vsalbaba]

I've added an issue for this https://github.com/xtf-cz/xtf/issues/563

[vsalbaba]

CI run - https://jenkins.eapqe.psi.redhat.com/view/EAP8/view/OpenShift/job/eap-8.x-openshift-4-80-openjdk17/536/

There are 4 tests failing, but they are consistent fails with current XTF - CI run with those jobs and current XTF - https://jenkins.eapqe.psi.redhat.com/view/EAP8/view/OpenShift/job/eap-8.x-openshift-4-80-openjdk17/537/

[mnovak1]

@vsalbaba Thanks, LGTM. Merging.