✨(plugin) add CommuneCreation plugin

Introduces some machinery for testing and executing API orchestrations.
Rolls back some changes in NameFromSiret plugin.

src/backend/people/settings.py

@@ -465,6 +465,21 @@ class Base(Configuration):
         environ_name="MAIL_PROVISIONING_API_CREDENTIALS",
         environ_prefix=None,
     )
+    DNS_PROVISIONING_API_URL = values.Value(
+        default="https://api.scaleway.com",
+        environ_name="DNS_PROVISIONING_API_URL",
+        environ_prefix=None,
+    )
+    DNS_PROVISIONING_RESOURCE_ID = values.Value(
+        default=None,
+        environ_name="DNS_PROVISIONING_RESOURCE_ID",
+        environ_prefix=None,
+    )
+    DNS_PROVISIONING_API_CREDENTIALS = values.Value(
+        default=None,
+        environ_name="DNS_PROVISIONING_API_CREDENTIALS",
+        environ_prefix=None,
+    )
 
     # Organizations
     ORGANIZATION_REGISTRATION_ID_VALIDATORS = json.loads(