message: Add ca-certificates to osx gitian descriptor
  [skip ci]
diff: @@ -26,6 +26,7 @@ packages:
  - "python-dev"
  - "python-setuptools"
  - "fonts-tuffy"
  +- "ca-certificates"
  reference_datetime: "2019-04-09 00:00:00"
  remotes:
  - "url": "https://github.com/BitcoinUnlimited/BitcoinUnlimited.git"
  