connection pool stops handling signals after while causing mqtt client to hang

[akrambek]

Describe the bug
The connection pool stops handling signals after while causing mqtt client to hang

To Reproduce
Steps to reproduce the behavior:

1. Setup cluster kafka with sasl plain setup
2. configure mqtt.kafka.broker example that connections to that cluster
3. Publish message using mosqueito_pub
4. Wait ~10 mins and connect
5. Client hangs