Problem: Netlify builds failing on UNSUPPORTED BUILD IMAGE

[weex]

Builds for my PR earlier today and master once it was merged failed with the following message.

1:31:19 PM: ---------------------------------------------------------------------
  UNSUPPORTED BUILD IMAGE

  The build image for this site uses Ubuntu 16.04 Xenial Xerus, which is no longer supported.

  To enable builds for this site, select a later build image at the following link:
  https://app.netlify.com/sites/rfczeromq/settings/deploys#build-image-selection

  For more details, visit the build migration guide:
  https://answers.netlify.com/t/please-read-end-of-support-for-xenial-build-image-everything-you-need-to-know/68239
  ---------------------------------------------------------------------

Proposed solution:
Update to a later build image.