fix(platform): preserve no-delete label when migration 43 stamps version

Address review feedback from lexfrei on migrations/43: the version stamp
did a label-less `kubectl create configmap | kubectl apply` under the same
field manager migration 42 used, stripping the platform.cozystack.io/no-delete
label and dropping cozystack-version out of the deletion-protection guardrail on
every upgrade through this migration. Replace it with a labeled heredoc manifest
mirroring migration 42 so the label survives the stamp.

Assisted-By: Claude <noreply@anthropic.com>
Signed-off-by: Myasnikov Daniil <myasnikovdaniil2001@gmail.com>

packages/core/platform/images/migrations/migrations/43

@@ -27,6 +27,21 @@ for ns in $(kubectl get cluster.postgresql.cnpg.io -A \
   fi
 done
 
-# Stamp version
-kubectl create configmap -n cozy-system cozystack-version \
-  --from-literal=version=44 --dry-run=client -o yaml | kubectl apply -f-
+# Stamp version.
+# Mirror migration 42's labeled manifest. A label-less apply by the same field
+# manager (kubectl create | kubectl apply) would strip the
+# platform.cozystack.io/no-delete label migration 42 added, dropping
+# cozystack-version out of the cozystack-no-delete-guardrail
+# ValidatingAdmissionPolicy. templates/cozystack-version.yaml only re-renders the
+# labeled ConfigMap on first install, so the label must be carried inline here.
+kubectl apply --filename - <<EOF
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: cozystack-version
+  namespace: cozy-system
+  labels:
+    platform.cozystack.io/no-delete: "true"
+data:
+  version: "44"
+EOF