Make apprise an official requirement for the framewokrk.

#2

Author: iTerminate

tools/developer_tools/bely-mqtt-message-broker/requirements.txt

@@ -5,9 +5,7 @@ pydantic>=2.0.0
 python-dotenv>=1.0.0
 pluggy>=1.3.0
 PyYAML>=6.0.3
-
-# Optional: For notification support
-# apprise>=1.4.0
+apprise>=1.4.0
 
 # Development dependencies (install with: pip install -e ".[dev]")
 # pytest>=7.0.0