When run, this container puts a message on an azure service bus topic.
This container uses environment variables to pass in the service bus information.
MessageBusConnectionString This is the connection string to the message bus.
MessageBusTopic This is the topic that the message will be placed on.
MessageBody This is the content of the message.
MessageLabel This is the label on the message, you can use this to filter messages to a certain subscription. If not supplied, no label will be set.