In case when dht::boot_strapper::get_boostrap_tokens fail to parse the
tokens, the topology coordinator handles the exception and schedules a
rollback. However, the current code tries to continue with the topology
coordinator logic even if an exception occurs, leaving boostrap_tokens
empty. This does not make sense and can actually cause issues,
specifically in prepare_and_broadcast_cdc_generation_data which
implicitly expect that the bootstrap_tokens of the first node in the
cluster will not be empty.
Fix this by adding the missing break.
Fixes: scylladb/scylladb#23897
From the code inspection alone it looks like 2025.1 and 6.2 have this problem, so marking for backport to both of them.
Closesscylladb/scylladb#23914
* https://github.com/scylladb/scylladb:
test: cluster: add test_bad_initial_token
topology coordinator: do not proceed further on invalid boostrap tokens
cdc: add sanity check for generating an empty generation