Failing deployment gives unhelpful message

[Shirikatsu]

Attempting to use truffle-keystore-provider as the provider in truffle-config.js with a https endpoint is failing with this error message:

$ openzeppelin push --network development --deploy-dependencies --skip-compile
...
✖ Deploying openzeppelin-eth dependency to network dev-444900
Failed deployment of dependency openzeppelin-eth with error: [object Object]

The returned object is completely obfuscated and prevents proper debugging.

I would expect the json object to be returned properly.