Fix iOS app crashing on None values in Zeroconf service info (#36490)

homeassistant/components/zeroconf/__init__.py

@@ -120,10 +120,10 @@ def setup(hass, config):
 
     params = {
         "version": __version__,
-        "external_url": None,
-        "internal_url": None,
+        "external_url": "",
+        "internal_url": "",
         # Old base URL, for backward compatibility
-        "base_url": None,
+        "base_url": "",
         # Always needs authentication
         "requires_api_password": True,
     }