added configuration for Gradle Test-Retry plugin to ConventionsPlugin.
Comment From: wilkinsona
Thanks for your efforts here, @mikesmithson. Unfortunately, the latest updates do not get things working. The test retry plugin isn't being applied so they have no effect. When it is applied, a failure occurs as the extension is on the Test task not the Project. I've made the necessary changes in https://github.com/spring-projects/spring-boot/commit/9bdf4a75e8a1bbada77bc8128e6dc2321e6222e0. Thanks anyway.
Comment From: mikesmithson
@wilkinsona - thanks, I gave it a shot. Was my first attempt at doing something like this.