DevKit updates

docs/.doctor-rst.yaml

@@ -16,7 +16,6 @@ rules:
     ensure_order_of_code_blocks_in_configuration_block: ~
     american_english: ~
     valid_use_statements: ~
-    yaml_instead_of_yml_suffix: ~
     extend_abstract_admin: ~
     final_admin_class: ~
     final_admin_extension_classes: ~
@@ -26,6 +25,7 @@ rules:
     no_inheritdoc: ~
 
     # can be enabled when no Symfony 3.4 support anymore
+    #yaml_instead_of_yml_suffix: ~
     #no_app_bundle: ~
     #no_config_yaml: ~
     #kernel_instead_of_app_kernel: ~