fix(spark): remove the JRE before installing the JDK

[razvan]

Description

Fixes this error when building images with Java 21:

Reusable Workflow / Build/Publish 4.0.1-amd64 Image     UNKNOWN STEP    2026-01-26T14:55:35.8200975Z #111 10.31 error: Error running transaction: file /usr/lib/.build-id/0f/5bf41e3e207feb6cab260b2366f1697c13555b from install of temurin-21-jdk-21.0.10.0.0.7-1.x86_64 conflicts with file from package temurin-21-jre-21.0.10.0.0.7-1.x86_64

⌛ Image build run: https://github.com/stackabletech/docker-images/actions/runs/21366173286

Definition of Done Checklist

Note

Not all of these items are applicable to all PRs, the author should update this template to only leave the boxes in that are relevant.

Please make sure all these things are done and tick the boxes

• Changes are OpenShift compatible
• All added packages (via microdnf or otherwise) have a comment on why they are added
• Things not downloaded from Red Hat repositories should be mirrored in the Stackable repository and downloaded from there
• All packages should have (if available) signatures/hashes verified
• Add an entry to the CHANGELOG.md file
• Integration tests ran successfully

TIP: Running integration tests with a new product image

The image can be built and uploaded to the kind cluster with the following commands:

boil build <IMAGE> --image-version <RELEASE_VERSION> --strip-architecture --load
kind load docker-image <MANIFEST_URI> --name=<name-of-your-test-cluster>

See the output of boil to retrieve the image manifest URI for <MANIFEST_URI>.