Update artifacts/api-templates/sample-implicit-events.yaml

Co-authored-by: Herbert Damker <herbert.damker@telekom.de>

Author: PedroDiez

artifacts/api-templates/sample-implicit-events.yaml

@@ -422,9 +422,9 @@ components:
             resource without event notifications.
 
             If provided, the API provider SHOULD support event delivery. If
-            notification delivery is not supported, the request is rejected
-            with `422 EVENT_NOTIFICATIONS_NOT_SUPPORTED` and the resource is NOT
-            created.
+            notification delivery is not supported, the request MUST be rejected
+            with `422 EVENT_NOTIFICATIONS_NOT_SUPPORTED` and the resource MUST NOT
+            be created.
           allOf:
             - $ref: "../common/CAMARA_event_common.yaml#/components/schemas/Sink"
         sinkCredential: