This test limits `commitlog_segment_size_in_mb` to 2, thus `max_command_size`
is limited to less than 1 MB. It adds an injection which copies mutations
generated by `get_cdc_generation_mutations` n times, where n is picked that
the memory size of all mutations exceeds `max_command_size`.
This test passes if cdc generation data is committed by raft in multiple commands.
If all the data is committed in a single command, the leader node will loop trying
to send raft command and getting the error:
```
storage_service - raft topology: topology change coordinator fiber got error raft::command_is_too_big_error (Command size {} is greater than the configured limit {})
```
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