message: [api] Fix build script
  I was getting errors when running `yarn build` locally because the public directory already exists.
  This will make sure the public directory is deleted before generating it again.
diff: @@ -76,7 +76,7 @@ async function main() {
  }
  execSync(
  - `mkdir public && echo '<a href="https://zeit.co/new">https://zeit.co/new</a>' >> public/index.html`
  + `rm -rf public && mkdir public && echo '<a href="https://zeit.co/new">https://zeit.co/new</a>' > public/index.html`
  );
  }
  