Cleaner CI logs: enroll to Gradle Enterprise and stop building with '-i'

[mockitoguy]

Let's clean up the CI logs. How about we enroll to Gradle Enterprise and avoid building with '-i' parameter (it's --info level logging).

Info level logging is noisy and rarely needed. For example, the checkstyle task logs the entire XSL transformation at info level.

[epeee]

+1, I like the idea.