Update the main EdgeX diagram

[jumpingliu]

📚 Docs or Wiki Bug Report

Description [REQUIRED]

https://docs.edgexfoundry.org/3.1/about/#edgex-foundry-service-layers The main EdgeX diagram is out of date. Here's the list of what's needed to be updated:

• Added “Message Bus” which is the common internal communication mechanism and database as a part of the Core Services.
• Removed the arrow suggesting that device data always goes to Core Data
• Removal of System Management panel, since the SMA was deprecated and removed in V3.0 (we no longer have a section for it in docs)
• Update the list of device services to the ones actually provided (it was a very old list before).
• Rename “Alerts & Notifications” to just “Notifications” as per how it is now described in docs

What's the affected URL? [REQUIRED]

https://docs.edgexfoundry.org/3.1/about/#edgex-foundry-service-layers