Small updates to conformance test for scs-0214-v1

[cah-hbaum]

We need to update the conformance test for scs-0214-v1 done in #486 , since there were some relevant but non-critical comments.

• Remove "internal" config (Create conformance test for scs-0214-v1 #486 (comment) and Create conformance test for scs-0214-v1 #486 (comment))
  The config used in the code is a duplication of the one used during the input. Either we remove it and require a config to be inputed or the "internal" config is narrowed down.

• Introduce another source for labels-by-node list (Create conformance test for scs-0214-v1 #486 (review))
  The labels-by-node list should be able to come from other sources and not only the get_k8s_cluster_labelled_nodes()

• Think about the possibility to provide some scenarios to test this test

Definition of Done:

• Test is updated with reference to the comments from Create conformance test for scs-0214-v1 #486
• PR created
• Changes have been reviewed and merged