gradle-enterprise-gradle-plugin is required

Can be patched out just to see what the next build failure is, but does not build without it. Used to be known as com.gradle.build-scan before v6 and now appears to be proprietary? or at least it's made clear that you need to agree to https://scans.gradle.com/ ToS.

Upstream says compilation without gradle-enterprise should work, so we should try to do it with the latest version without any other patches: no debian changes, no 6.4.1 - just try upstream master / latest tag without gradle-enterprise using their build system/bootstrap binaries, see if that works