We use curl in our integration test script to make sure the application container is
available before moving on. We expect many connection errors and don't care
about the output of curl, so this will just swallow all of the output.
Eventually, this should replace the CircleCI config for running the
integration tests to avoid duplication. In the interest of time so that
I don't have to debug broken builds, I'm only adding it as a utility
script.
