Remove `org.apache.druid.discovery.BrokerClient` by switching to `org.apache.druid.sql.client.BrokerClient`

[abhishekrb19]

org.apache.druid.discovery.BrokerClient was deprecated in favor of org.apache.druid.sql.client.BrokerClient in #17382.

Currently, there's only one usage of org.apache.druid.discovery.BrokerClient in SegmentLoadStatusFetcher in the MSQ code. We can remove that instance altogether and migrate to using the new org.apache.druid.sql.client.BrokerClient which is a more robust client.

[5AIPAVAN]

can i work on this @abhishekrb19 :-) ( i am a beginner )
please assign me this

[satwik-codeium]

Fix here: #17470

[akulabs8]

Hey , still open, can i take it up?

[tarunk8924]

Fix here : #17681