fix(drain nemesis): remove check_cluster_health() call
fix(drain nemesis): remove check_cluster_health() call

Since always after drain the node being drain isn't reachable,
no point of doing `check_cluster_health()` as is, it would always fail to reach this one node.

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