Review tuning of JVM parameters for the build

Description

The Gradle daemon was frequently logging needing to be restarted because of OOM, and a quick check with JConsole also revealed that we're giving way too much memory for the testsuite runners - especially or metaspace.

We can re-balance things out, to make the warnings disappear and hopefully recover a bit of build efficiency.

Environment

None
Fixed

Assignee

Sanne Grinovero

Reporter

Sanne Grinovero

Fix versions