[yamllint] tests/unit/settings/user_settings_simple.yml

Fixed messages reported by::

    make test.yamllint

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

tests/unit/settings/user_settings_simple.yml

@@ -1,9 +1,9 @@
-use_default_settings: True
+use_default_settings: true
 server:
-    secret_key: "user_secret_key"
-    bind_address: "0.0.0.0"
-    default_http_headers:
-        Custom-Header: Custom-Value
+  secret_key: "user_secret_key"
+  bind_address: "0.0.0.0"
+  default_http_headers:
+    Custom-Header: Custom-Value
 result_proxy:
-   url : https://localhost/morty
-   key : "$ecretKey"
+  url: https://localhost/morty
+  key: "$ecretKey"