Add CONTROL_CENTER_JMX_HOSTNAME and CONTROL_CENTER_JMX_PORT for easy JMX setup

[james-johnston-thumbtack]

The Schema Registry images support setting environment variables SCHEMA_REGISTRY_JMX_HOSTNAME and SCHEMA_REGISTRY_JMX_PORT to easily expose JMX metrics for the service. The code in Schema Registry is below:

https://github.com/confluentinc/schema-registry-images/blob/v7.5.2/schema-registry/include/etc/confluent/docker/launch#L17-L34

The corresponding launch script for Control Center does not have a similar feature:

https://github.com/confluentinc/control-center-images/blob/v7.5.2/control-center/include/etc/confluent/docker/launch

Could it be added?