Fix not working example of get "eth_accounts"

[MatthieuScarset]

Cannot use await inside the server function when using Ganache as a JSON-RPC web server.

[davidmurdoch]

This should probably be:

server.listen(PORT, async (err) => {
  if (err) throw err;
  console.log(`ganache listening on port ${PORT}...`);
  const provider = server.provider;
  const accounts = await provider.request({
    method: "eth_accounts",
    params: []
  });

[davidmurdoch]

Thanks for bringing this to our attention. I'm closing in favor of: #2789