fix: remove preserveUnknownFields (#774)

Author: moolen

charts/kubernetes-external-secrets/crds/kubernetes-client.io_externalsecrets_crd.yaml

@@ -10,8 +10,6 @@ spec:
   group: kubernetes-client.io
   scope: Namespaced
 
-  preserveUnknownFields: false
-
   versions:
     - name: v1
       served: true
@@ -203,4 +201,3 @@ spec:
     kind: ExternalSecret
     plural: externalsecrets
     singular: externalsecret
-