json-schema: Experiencing "Error: JSON schema not found at file://"

When updating our dependencies from 5.2.1 to 5.2.2 today, we experienced this error:

Error: JSON schema not found at file://

Ref https://github.com/wp-cli/wp-cli/pull/4393 and https://travis-ci.org/wp-cli/wp-cli/jobs/282809129

Let me know what situational details I can provide to help reproduce it. justinrainbow/json-schema is a dependency of Composer, which we use within our application.