Remove phocas-lustrum

The folder went in April (bb308a3) but the app and its DNS record stayed,
so the demo site kept serving at phocaslustrum.rubenhensen.nl.

apps/templates/phocas-lustrum-folder.yaml

@@ -1,21 +0,0 @@
-apiVersion: argoproj.io/v1alpha1
-kind: Application
-metadata:
-  name: phocas-lustrum
-  namespace: argocd
-  finalizers:
-  - resources-finalizer.argocd.argoproj.io
-spec:
-  project: default
-  source:
-    repoURL: https://github.com/rubenhensen/k8scd.git
-    targetRevision: HEAD
-    path: phocas-lustrum
-  destination:
-    server: https://kubernetes.default.svc
-    namespace: phocas-lustrum
-  syncPolicy:
-    syncOptions:
-    - CreateNamespace=true
-    automated:
-      selfHeal: true