fix(sdcm/cluster_k8s/mini_k8s.py): address pylint issues
fix(sdcm/cluster_k8s/mini_k8s.py): address pylint issues

scylladb/scylla-longevity-tests,scylladb/scylla-cluster-tests,scylladb/scylla-cluster-tests,scylladb/scylla-cluster-tests,scylladb/scylla-longevity-tests,scylladb/scylla-cluster-tests,scylladb/scylla-longevity-tests,scylladb/scylla-cluster-tests