Fix two issues with the replace operation introduced by recent PRs.
Add a test which performs a sequence of basic topology operations (bootstrap,
decommission, removenode, replace) in a new suite that enables the `raft`
experimental feature (so that the new topology change coordinator code is used).
Fixes: #13651Closes#13655
* github.com:scylladb/scylladb:
test: new suite for testing raft-based topology
test: remove topology_custom/test_custom.py
raft topology: don't require new CDC generation UUID to always be present
raft topology: include shard_count/ignore_msb during replace
ce94a2a5b0