In `ConsumerBuilder.build`, if `awaitInitialPositions` raises an exception, the consumer will not be closed properly. We should add the consumer instance to the `consumers` collection immediately after construction.
### Committer Checklist (excluded from commit message) - [ ] Verify design and implementation - [ ] Verify test coverage and CI build status - [ ] Verify documentation (including upgrade notes) [ Full content available at: https://github.com/apache/kafka/pull/5750 ] This message was relayed via gitbox.apache.org for devnull@infra.apache.org
