Trying to get cassandra active, idle, inUse connection

Please answer these questions before submitting your issue. Thanks!

### What version of Cassandra are you using?
Apache Cassandra 4.1

### What version of Gocql are you using?
1.6.0

### What version of Go are you using?
go version go1.22.3 darwin/arm64

### What did you do?
Trying to get cassandra active, idle, inUse connection.

### What did you expect to see?
get cassandra active, idle, inUse connection.

### What did you see instead?
Nothing found.
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If you are having connectivity related issues please share the following additional information

### Describe your Cassandra cluster
please provide the following information

- Get active connections
- Get Idle connections
- Get in-use connection.

Start by reviewing the GoCQL 1.6.0 driver documentation and connection-pool API for Cassandra 4.1. Clarify how active, idle, and in-use connections should be defined and exposed; the work is done when those counts are available with documented behavior and coverage.

Written by the indexing model from the issue text.