Use junit-bom for JUnit dependencies.

[Javaru]

With the changed to using JUnit 5 in 2023, it would be preferable to use the junit-bom for managing all JUnit dependencies.

BOM (Bill of Materials) files make version management easier -- since when upgrading JUnit, a version number change is only needed in one place -- and ensure a consistent version of JUnit artifacts are used throughout the project, even when pulled in transitively. For example, if a user where to add an additional testing library or framework that transitively pulls in (as an example) version 5.6.3 of junit-vintage-engine, the BOM would result in that being upgraded to the same version as the BOM, v5.8.2 in this example. Without the BOM, version 5.6.2 of junit-vintage-engine would get used, resulting in a mismatch of JUnit artifacts.

References:

• JUnit 5 User Guide §10.2.4. Bill of Materials (BOM)
• Gradle User Guide Using bills of materials (BOMs)
• Gradle Goodness: Use Bill of Materials (BOM) as Dependency Constraints
• Using Maven’s Bill of Materials (BOM)
  • A detailed article explaining the benefits of BOMs.
  • While this article focuses on BOMs use in Maven, the concepts apply to Gradle as well

[PeterJohnson]

We need to understand how this interacts with the installer, which needs to grab specific artifact versions for offline installation.

[ThadHouse]

I think this would work, but since we're not doing another beta cycle, I'd be worried about doing this so late. I think this might need to be a 2024 thing.