Removed unnecessary integrations serializer

refs: https://github.com/TryGhost/Toolbox/issues/245

- we don't need this serializer because the default serializer will call the integrations mapper

core/server/api/canary/utils/serializers/output/index.js

@@ -21,10 +21,6 @@ module.exports = {
         return require('./db');
     },
 
-    get integrations() {
-        return require('./integrations');
-    },
-
     get pages() {
         return require('./pages');
     },

core/server/api/canary/utils/serializers/output/integrations.js

@@ -1,25 +0,0 @@
-const debug = require('@tryghost/debug')('api:canary:utils:serializers:output:integrations');
-const mappers = require('./mappers');
-
-module.exports = {
-    all(models, apiConfig, frame) {
-        debug('all');
-
-        if (!models) {
-            return;
-        }
-
-        if (models.meta) {
-            frame.response = {
-                integrations: models.data.map(model => mappers.integrations(model, frame)),
-                meta: models.meta
-            };
-
-            return;
-        }
-
-        frame.response = {
-            integrations: [mappers.integrations(models, frame)]
-        };
-    }
-};

core/server/api/canary/utils/serializers/output/mappers/integrations.js

@@ -1,5 +1,5 @@
 module.exports = (model, frame) => {
-    const jsonModel = model.toJSON ? model.toJSON(frame.options) : model;
+    const jsonModel = model.toJSON(frame.options);
 
     if (jsonModel.api_keys) {
         jsonModel.api_keys.forEach((key) => {