Deprecated callback removed for MQTT subscribe (#1692)

* Deprecated callback removed for MQTT subscribe

* Update blog/2023-02-21-deprecated-callback-removed.md

Co-authored-by: Erik Montnemery <erik@montnemery.com>

---------

Co-authored-by: Erik Montnemery <erik@montnemery.com>

blog/2023-02-21-deprecated-callback-removed.md

@@ -0,0 +1,33 @@
+---
+author: Jan Bouwhuis
+authorURL: https://twitter.com/jbouwh
+title: Deprecated callback signatures for MQTT subscribe removed
+---
+
+Home Assistant's MQTT integration [no longer supports](https://github.com/home-assistant/core/pull/88543)
+deprecated callback signatures for MQTT subscribe.
+
+Custome integrations that still used the deprecated callback signature for the callback function on MQTT subscribe will break unless updated. An exception will be raised if a not supported callback type is detected.
+
+Examples of deprecated callback functions that will no longer work:
+
+```python
+async def async_deprecated_callback1(topic: str, payload: ReceivePayloadType, qos: int) -> None:
+    """Deprecated async callback example 1."""
+    ...
+
+
+@callback
+def async_deprecated_callback2(topic: str, payload: ReceivePayloadType, qos: int) -> None:
+    """Deprecated async callback example 2."""
+    ...
+```
+
+Example of a correct callback signature:
+
+```python
+@callback
+def async_correct_callback(msg: msg: ReceiveMessage) -> None:
+    """Callback example 1."""
+    ...
+```