Add GraalVM flavor as base container image

[XhstormR]

It would be great if we have gradle image with GraalVM.

FYI:
https://github.com/graalvm/graalvm-ce-builds/releases/tag/jdk-20.0.2
https://github.com/graalvm/container

[keeganwitt]

Forgive the ignorance (I'm not a Graal user), but isn't Graal only needed for runtime and not build time?

Another challenge I'd have for implementing this request is that as an official image, I'm only allowed to extend other official images, and I don't see one for Graal.

[XhstormR]

@keeganwitt According to this PR oracle/graal#5995 , Native Image is now shipped as part of the GraalVM JDK and thus no longer needs to be installed via gu install native-image. So we can use native-image tools to directly convert the jar file into a native executable file after the gradle build is complete.

[keeganwitt]

Adding link here for posterity: the idea of an official GraalVM image was rejected previously.
docker-library/official-images#10936

I'm discussing with the Docker Library folks whether my installing GraalVM in an official Gradle image would be problematic.