Cannot get Pushover to work
## Alarm system
EVO192 7.70.1 + IP150

## Environment
Docker (latest) on Raspberry Pi 4 

## Describe the bug
Using configuration below I get two lines of logging related to Pushover but no notification is sent.
Please note test notifications from Pushover website are correctly delivered.

## To Reproduce
```
PUSHOVER_ENABLE = True
PUSHOVER_KEY = '<Application token>'
PUSHOVER_BROADCAST_KEYS = [{
   'user_key': '<User key>',
   'devices': '*'
}]
PUSHOVER_MIN_EVENT_LEVEL = 'DEBUG'
```
## Logs
```
pai  | 2024-04-09 18:41:20,603 - DEBUG    - MainThread - PAI.paradox.interfaces.interface_manager - Registering PushoverTextInterface
pai  | 2024-04-09 18:41:20,604 - INFO     - PushoverTextInterface - PAI.paradox.interfaces - Starting PushoverTextInterface Interface
```