Run tests serial-y

So we don’t get errors about ports already being in use

package.json

@@ -10,7 +10,7 @@
   ],
   "scripts": {
     "build": "lerna run build",
-    "test": "lerna run test",
+    "test": "lerna run test --concurrency 1",
     "prepare": "yarn build"
   },
   "dependencies": {},