update c8y tedge scan output to reflect current implementation

Signed-off-by: Reuben Miller <reuben.d.miller@gmail.com>

docs/src/extend/firmware-management/device-onboarding.md

@@ -94,13 +94,13 @@ On your machine (not the target device that will be on-boarded) you will need on
  ```
 
  ```sh title="Output"
- rpi1-b827eb21100e
- rpi2-b827ebed6e5a
- rpi3-b827ebe1f7d6
- rpi4-dcb630486720
- rpi5-d83add9a145a
- rpizero-b827ebdddb46
- rpizero2-d83add030bfd
+ rpi1-b827eb21100e.local
+ rpi2-b827ebed6e5a.local
+ rpi3-b827ebe1f7d6.local
+ rpi4-dcb630486720.local
+ rpi5-d83add9a145a.local
+ rpizero-b827ebdddb46.local
+ rpizero2-d83add030bfd.local
  ```
 
  :::info