[CLI-2818] Add `flink statement update`

[brianstrauch]

Release Notes

Breaking Changes

• PLACEHOLDER

New Features

• Add confluent flink statement update for updating a statement's principal and compute pool, or stopping a statement

Bug Fixes

• PLACEHOLDER

Checklist

1. [CRUCIAL] Is the change for features that are already live in prod?
   • no: DO NOT MERGE until the required features are live in prod

What

• Add confluent flink statement update --principal [u-123456|sa-123456]
• Add confluent flink statement update --compute-pool
• Add confluent flink statement update --stopped=[true|false]

References

https://confluentinc.atlassian.net/browse/CLI-2818

Test & Review

Integration tests, waiting for backend to be ready before merging.