springboot Test the Gradle Plugin against Gradle 6.1

Hi,

Gradle 6.1 was released earlier this night, so I guess we can test against it.

Cheers, Christoph

Comment From: wilkinsona

Thanks, @dreis2211. Would you mind reworking this so that it's based on 2.2.x? For master we'll update the build to use Gradle 6.1 (so default will be 6.1) and add 6.0.1 as another version to test again (#19772).

Comment From: dreis2211

If I wouldn't screw up my branch while doing so, I'd of course do that 😆 I guess I have to open a new PR, sorry.

Comment From: dreis2211

Closing in favor of #19776