Update patchmon to 2.1.3

Chart rewrite for the 2.x single-server architecture: one stateless
server deployment (frontend embedded, /api served by the same process),
no PVC, single service and ingress path, optional guacd sidecar
(disabled by default), 2.x env vocabulary (TRUST_PROXY, readonly role),
probes send the public hostname as Host header.

Fixes #29: all three reported spots (PVC storageClass guard, RWX assets
PVC, frontend nginx 'backend' hostname) are removed by this rewrite.

patchmon/templates/patchmon.service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ .Release.Name }}-{{ .Chart.Name }}-service
+spec:
+  selector:
+    app: {{ .Release.Name }}-{{ .Chart.Name }}
+  ports:
+    - protocol: TCP
+      port: 80
+      targetPort: http
+      name: http
+  type: ClusterIP