Reduce usage of executer threads in AVM Fritz!Tools (#114570)

* call entity state update calls in one executer task

* remove not needed wrapping

* mark as "non-public" method

* add guard against changes on _entity_update_functions

homeassistant/components/fritz/common.py

@@ -311,6 +311,17 @@ class FritzBoxTools(
                 )
         return unregister_entity_updates
 
+    def _entity_states_update(self) -> dict:
+        """Run registered entity update calls."""
+        entity_states = {}
+        for key in list(self._entity_update_functions):
+            if (update_fn := self._entity_update_functions.get(key)) is not None:
+                _LOGGER.debug("update entity %s", key)
+                entity_states[key] = update_fn(
+                    self.fritz_status, self.data["entity_states"].get(key)
+                )
+        return entity_states
+
     async def _async_update_data(self) -> UpdateCoordinatorDataType:
         """Update FritzboxTools data."""
         entity_data: UpdateCoordinatorDataType = {
@@ -319,15 +330,9 @@ class FritzBoxTools(
         }
         try:
             await self.async_scan_devices()
-            for key in list(self._entity_update_functions):
-                _LOGGER.debug("update entity %s", key)
-                entity_data["entity_states"][
-                    key
-                ] = await self.hass.async_add_executor_job(
-                    self._entity_update_functions[key],
-                    self.fritz_status,
-                    self.data["entity_states"].get(key),
-                )
+            entity_data["entity_states"] = await self.hass.async_add_executor_job(
+                self._entity_states_update
+            )
             if self.has_call_deflections:
                 entity_data[
                     "call_deflections"