XD-3023: Restore SSL to RabbitMessagBus
JIRA: XD-3023">https://jira.spring.io/browse/XD-3023
Prior to XD-2381, XD had its own version of `RabbitConnectionFactoryBean`, which
predated the Spring AMQP version.
XD-2381 switched the bus to use the Spring AMQP version but the configuration of
`useSSL` and `sslProperties` was lost (the XD version of the FB injected these
properties using `@Value` injection).
Restore these properties via the `ConnectionFactorySettings` configuration bean.