Add integration_type service to dexcom (home-assistant#158928)

Author: joostlek

homeassistant/components/dexcom/manifest.json

@@ -4,6 +4,7 @@
   "codeowners": ["@gagebenne"],
   "config_flow": true,
   "documentation": "https://www.home-assistant.io/integrations/dexcom",
+  "integration_type": "service",
   "iot_class": "cloud_polling",
   "loggers": ["pydexcom"],
   "requirements": ["pydexcom==0.2.3"]

homeassistant/generated/integrations.json

@@ -1326,7 +1326,7 @@
     },
     "dexcom": {
       "name": "Dexcom",
-      "integration_type": "hub",
+      "integration_type": "service",
       "config_flow": true,
       "iot_class": "cloud_polling"
     },