fix spec, add json schema

spec/fixtures/api/schemas/geo_project_registry.json

+{
+  "type": "array",
+  "required" : [
+    "project_id",
+    "last_repository_synced_at",
+    "last_repository_successful_sync_at",
+    "last_wiki_synced_at",
+    "last_wiki_successful_sync_at",
+    "repository_retry_count",
+    "wiki_retry_count",
+    "last_repository_sync_failure",
+    "last_wiki_sync_failure"
+  ],
+  "properties" : {
+    "project_id": { "type": "integer" },
+    "last_repository_synced_at": { "type": ["string"] },
+    "last_repository_successful_sync_at": { "type": ["string"] },
+    "last_wiki_synced_at": { "type": ["string"] },
+    "last_wiki_successful_sync_at": { "type": ["string"] },
+    "repository_retry_count": { "type": "integer" },
+    "wiki_retry_count": { "type": "integer" },
+    "last_repository_sync_failure": { "type": ["string"] },
+    "last_wiki_sync_failure": { "type": ["string"] }
+  },
+  "additionalProperties": false
+}

spec/requests/api/geo_nodes_spec.rb

@@ -98,13 +98,13 @@ describe API::GeoNodes, :geo, api: true do
       get api("/geo_nodes/#{secondary.id}/failures", admin)
 
       expect(response.status).to eq 200
-      expect(response.body).to eq('')
+      expect(response).to match_response_schema('geo_project_registry')
     end
 
     it 'denies access if not admin' do
-      get api('/geo_nodes', user)
+      get api("/geo_nodes/#{secondary.id}/failures", user)
 
-      expect(response.failures).to eq 403
+      expect(response.status).to eq 403
     end
   end
 end