Mark auth voluptuous schema fields as required (#57003)

homeassistant/auth/providers/insecure_example.py

@@ -1,7 +1,6 @@
 """Example auth provider."""
 from __future__ import annotations
 
-from collections import OrderedDict
 from collections.abc import Mapping
 import hmac
 from typing import Any, cast
@@ -117,10 +116,13 @@ class ExampleLoginFlow(LoginFlow):
                 user_input.pop("password")
                 return await self.async_finish(user_input)
 
-        schema: dict[str, type] = OrderedDict()
-        schema["username"] = str
-        schema["password"] = str
-
         return self.async_show_form(
-            step_id="init", data_schema=vol.Schema(schema), errors=errors
+            step_id="init",
+            data_schema=vol.Schema(
+                {
+                    vol.Required("username"): str,
+                    vol.Required("password"): str,
+                }
+            ),
+            errors=errors,
         )