fix: make type checking faster and more portable

Author: Evgeny Markov

package.json

@@ -5,8 +5,8 @@
   "main": "index.js",
   "types": "index.d.ts",
   "scripts": {
-    "test": "standard && tap -J test/*.test.js && npm run test:types",
-    "test:types": "sh tools/build-examples.sh",
+    "test": "standard && tap -J test/*.test.js && npm run test:typescript",
+    "test:typescript": "tsc --build examples/typescript/*",
     "test:report": "standard && tap -J --coverage-report=html test/*.test.js",
     "test:verbose": "standard && tap -J test/*.test.js -Rspec",
     "postgres": "docker run -p 5432:5432 --name fastify-postgres -e POSTGRES_PASSWORD=postgres -d postgres:11-alpine",