Fix PROJECT file

Author: lucian-tosa

PROJECT

@@ -4,7 +4,7 @@
 # More info: https://book.kubebuilder.io/reference/project-config.html
 domain: mongodb.com
 layout:
-- go.kubebuilder.io/v4
+- go.kubebuilder.io/v3
 plugins:
   manifests.sdk.operatorframework.io/v2: {}
   scorecard.sdk.operatorframework.io/v2: {}