Make identity deletion replay safe

identity-provisioner/provisioner.py

@@ -153,10 +153,15 @@ mutation Remove($userId: String!, $groupId: Int!) {
         return list(value["users"]), list(value["groups"])
 
     def _user(self, token: str, subject: str) -> dict[str, Any] | None:
-        value = self._gql(token, """
+        try:
+            value = self._gql(token, """
 query User($id: String!) {
   user(userId: $id) { id email displayName groups { id displayName } }
 }""", {"id": subject})
+        except ValueError as exc:
+            if "not found" in str(exc).lower():
+                return None
+            raise
         user = value.get("user")
         return dict(user) if user else None