Az event hub partition keys are limited to a max of 128 chars.
When debezium tries to send a partition key longer than 128 chars, it throws an exception and terminates the connector. 

This implements a new feature to optionally hash message keys to better support usage of the sink.
New optional sink configs:

• debezium.sink.eventhubs.hashmessagekey=true # false by default – when enabled, message keys will be hashed using the specified hash function
• debezium.sink.eventhubs.hashmessagekeyfunction=java # java by default – supported values: java, md5, sha1, sha256