message: Update Tinkey URL and hash for Tink 1.7.0.
diff: class Tinkey < Formula
  desc "A command line tool to generate and manipulate keysets for the Tink cryptography library"
  homepage "https://github.com/google/tink/tree/master/tools/tinkey"
  - url "https://storage.googleapis.com/tinkey/tinkey-1.6.1.tar.gz"
  - sha256 "156e902e212f55b6747a55f92da69a7e10bcbd00f8942bc1568c0e7caefff3e1"
  + url "https://storage.googleapis.com/tinkey/tinkey-1.7.0.tar.gz"
  + sha256 "2c9e69e5bc7561ce37918cecd3eeabb4571e01c915c4397bce25796ff04d92a3"
  def install
  bin.install "tinkey"
  