fix(node decomission): stop a decommissioned node by default

[yarongilor]

A decommissioned node currently left is_running() after its status changed to "decommissioned". thus it is unexpectedly left as part of cluster nodes, like in cluster.nodelist(). This should not be the default, but rather to stop() the node after decommission successfully completed (as it is in SCT). This fix requires a corresponding dtest PR to adjust all calls of node.decommission() in order to remove 14 un-needed calls to node.stop() or to set the new flag of stop_node=False needed for raft testing. This fix is a followup of: https://github.com/scylladb/scylla-dtest/pull/4767#discussion_r1731340260 refs: https://github.com/scylladb/scylla-dtest/pull/4767#discussion_r1731340260

There are also 11 occurrences of nodetool("decommission") to be adjusted/optimized:

$ grep -Eri '\.nodetool\(.*decommission' --include \*.py .
./manager_backup_tests.py:        node3.nodetool("decommission")
./compaction_additional_test.py:                node2.nodetool("decommission")
./manager_restore_tests.py:        node3.nodetool("decommission")
./manager_restore_tests.py:        node3.nodetool("decommission")
./manager_restore_tests.py:            node.nodetool("decommission")
./update_cluster_layout_tests.py:        node1.nodetool("decommission")
./update_cluster_layout_tests.py:        node3.nodetool("decommission", capture_output=False, wait=False)
./update_cluster_layout_tests.py:        node3.nodetool("decommission", capture_output=False, wait=False)
./update_cluster_layout_tests.py:        node3.nodetool("decommission", capture_output=False, wait=False)
./nodetool_additional_test.py:        node2.nodetool("decommission")
./topology_test.py:            out, err = node.nodetool("decommission")

[fruch]

@yarongilor @pehala is this one still needed ?

[yarongilor]

@yarongilor @pehala is this one still needed ?

i guess it is still relevant. We just have to prioritize and schedule it along with a dtest PR.

[pehala]

i guess it is still relevant. We just have to prioritize and schedule it along with a dtest PR.

IF you want to progress with this please create dtest PR for this as well