Network indicator displays "LTE" icon/text even after the LTE connection is ended and the modem removed from the system

## What Happened
After disconnecting the LTE connection and unplugging the USB modem from the system, the network indicator still displays "LTE" in Wingpanel. If another connection is enabled, like WiFi, then both will be displayed the WiFi icon and "LTE" text/icon next to it.


## Expected Behavior
Once the LTE connection is ended and/or the LTE modem is unplugged no indication of LTE connection should be displayed in Wingpanel network indicator.

## Steps to Reproduce
1. Plug a LTE USB modem
2. Disable WiFi using the network indicator
3. Enable the LTE connection using the network indicator
4. Once the connection is established, browse the web a bit.
5. Disable the LTE connection using the network indicator
6. Unplug the USB LTE modem
7. Enable WiFi using the network indicator
8. Wait for the WiFi connection to be established

### Logs
N/A

## Platform Information
- elementary OS Odin 6 (up to date)
- wingpanel-indicator-network/focal,now 2.3.0+r741+pkg26~ubuntu6.1