fix (azure-iot-device): Prevent duplicate twin GET upon Connect

[cartertinney]

• Stages (except the MQTTTransportStage) now always invoke .send_event_up() at the end of the .handle_pipeline_event() call
• Now that connection state has been improved by previous PRs, we no longer have to work around timing issues by invoking .send_event_up() early
• By doing things in the correct order, we now will no longer be accidentally republishing the twin GET that triggers upon connection
• Fixes Unnecessary multiple downloads of twin data when setting on_twin_desired_properties_patch_received #994

[BertKleewein]