[discuss] BacklogQuota param change

[ZhangJian He]

I found a change between pulsar2.7 and pulsar2.9

command
```
bin/pulsar admin namespaces get-backlog-quotas $tenant/$namespace
```

pulsar2.7 returns `limit=1024, policy=consumer_backlog_eviction`

but pulsar 2.9 returns

```[root@23da8000c7c1 bin]# ./pulsar-admin namespaces get-backlog-quotas
public/functions
"destination_storage    BacklogQuotaImpl(limitSize=102400, limitTime=-1,
policy=consumer_backlog_eviction)"
```

I found that the @JsonAlias("limit") annotation has been removed
on org.apache.pulsar.common.policies.data.BacklogQuota in
https://github.com/apache/pulsar/pull/10774.
My question is, Is that a expected change or compatible change? I search
the 2.8.0 release notes, I didn't saw it.

And If it involves work, I'm happy to help :)


Thanks
ZhangJian He