fix(k8s): pick up really latest operator helm chart
fix(k8s): pick up really latest operator helm chart

For the moment, specifying scylla-operator chart as 'latest'
we get the oldest version in the family - '1.8.0-alpha.0'.
But it should be something like this - 'v1.8.0-alpha.0-47-g161d249'.

It leads to the situation that we use very old helm chart and newest
scylla-operator image. This situation is a bug.

So, fix it by ignoring all the versions which contain 1,2 and 4+ '-'
symbols. Also, check that we have the same 'v' prefix all the time.

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