attempt to fix next-js example deploy issue

examples/with-nextjs/vercel.json

@@ -1,3 +1,4 @@
 {
-  "outputDirectory": "build"
+  "outputDirectory": "build",
+  "installCommand": "yarn install && yarn --cwd ../../ install"
 }

examples/with-script-in-browser/vercel.json

@@ -1,5 +1,5 @@
 {
   "outputDirectory": "dist",
-  "installCommand": "yarn install",
+  "installCommand": "yarn install && yarn --cwd ../../ install",
   "buildCommand": "yarn build:packages && yarn build"
 }