Mark grafana's and home-assistant's soft requirements optional (hq issue 166, ADR 0330)

grafana runs without influxdb and home-assistant without the Servarr apps or a broker, yet a mesh
without them could not assign either. Their requirements are now optional: bound when a provider
runs, absent otherwise, with nothing installed for them. grafana's data source and its credential are
delivered only while influxdb-api is bound, into directories it mounts, so an absent file never
becomes a directory docker made in its place.

modules/home-assistant/module.json

@@ -123,11 +123,23 @@
     }
   ],
   "requires": [
-    "lidarr-api",
-    "mqtt-topic",
-    "radarr-api",
+    {
+      "name": "lidarr-api",
+      "optional": true
+    },
+    {
+      "name": "mqtt-topic",
+      "optional": true
+    },
+    {
+      "name": "radarr-api",
+      "optional": true
+    },
     "route",
-    "sonarr-api"
+    {
+      "name": "sonarr-api",
+      "optional": true
+    }
   ],
   "contributes": {
     "mqtt-topic": {