Add code format pass to GitHub test

[JamesSmartCell]

As per the web3j repo, which will fail PRs if the code isn't formatted correctly.

I was able to find these but not sure if it's JaCoCo that's doing the formatting pass.

https://github.com/micrometer-metrics/micrometer/commit/553db53196ac7e58cb546b7ed8c90a6ba6ee09bb https://stackoverflow.com/questions/40330470/jacoco-report-format