[releng] Maven build on ci.eclipse.org only works in one out of two runs

The maven build on ci.eclipse.org [1] often fails with a Java heap space error, see below. This is likely related to a missing explicit configuration of the required heap space.

[ERROR] Failed to execute goal org.eclipse.tycho:tycho-p2-director-plugin:4.0.3:archive-products (archive-products) on project org.eclipse.papyrus.designer.product: Error packing product: Problem creating zip: Execution exception: Java heap space -> [Help 1]

[1] https://ci.eclipse.org/papyrus/job/papyrus-designer-2023-03