Add script to compare alexa locales with upstream (#114247)

* Add script to compare alexa locales with upstream

* Use a function in script

* Add test base

* Complete output assertion

* Add type annotation

* Add note to docstring

* Update script call example

Co-authored-by: Jan Bouwhuis <jbouwh@users.noreply.github.com>

---------

Co-authored-by: Jan Bouwhuis <jbouwh@users.noreply.github.com>

homeassistant/components/alexa/capabilities.py

@@ -300,6 +300,10 @@ class Alexa(AlexaCapability):
     The API suggests you should explicitly include this interface.
 
     https://developer.amazon.com/docs/device-apis/alexa-interface.html
+
+    To compare current supported locales in Home Assistant
+    with Alexa supported locales, run the following script:
+    python -m script.alexa_locales
     """
 
     supported_locales = {