Revert "wait ssh up before starting journal and backtrace threads"
Revert "wait ssh up before starting journal and backtrace threads"

wait_ssh_up() in BaseNode init might raise exception for network issue,
it would cause Decommission test fails to add node back to cluster.
If this issue occurs 5 times, cluster will only leave one node, then
longevity test will break.

The wait_ssh_up() was introduced by commit fc1c754b, let's solve the
issue by revert the commit.

The original commit fc1c754b is used to reduce the chance to create
repeated master SSH, but we already improved start_master_ssh()
by commit 1adeb5df. So it's save to revert commit fc1c754b.

This reverts commit fc1c754b1e14537c6c29f4342dcb7aa7f834a17c.

Signed-off-by: Amos Kong <eb01d8f828a6c9a20be4534e72e049aaf41503df@scylladb.com>

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