The following incompatibilities were identified by `listsnapshots_test.py` in dtests:
* Command doesn't bail out when there are no snapshots, instead it prints meaningless empty report
* Formatting is incompatible
Both are fixed in this mini-series.
Closesscylladb/scylladb#17541
* github.com:scylladb/scylladb:
tools/scylla-nodetool: listsnapshots: make the formatting compatible with origin's
tools/scylla-nodetool: listsnapshots: bail out if there are no snapshots