Pin async-timeout to 4.0.3 (#129592)

Author: bdraco

homeassistant/package_constraints.txt

@@ -189,3 +189,7 @@ tuf>=4.0.0
 
 # https://github.com/jd/tenacity/issues/471
 tenacity!=8.4.0
+
+# 5.0.0 breaks Timeout as a context manager
+# TypeError: 'Timeout' object does not support the context manager protocol
+async-timeout==4.0.3

script/gen_requirements_all.py

@@ -205,6 +205,10 @@
 
 # https://github.com/jd/tenacity/issues/471
 tenacity!=8.4.0
+
+# 5.0.0 breaks Timeout as a context manager
+# TypeError: 'Timeout' object does not support the context manager protocol
+async-timeout==4.0.3
 """
 
 GENERATED_MESSAGE = (