We already have a technology-agnostic way to test different platforms in Pipelines using different Docker containers in multiple steps. I've added an example of how to test with different Java versions to our documentation.
Given this Docker-based solution works equally well for lots of different platforms, we don't have any plans to build support for specific technologies like Maven's toolchains in Pipelines at the moment.
Thanks @mryall_atlassian for adding an example to your documentation. However, for my particular use case, I do not think using different Docker containers would work. i.e. Maven 3.3+ requires JDK 7+ to execute, but my target version is JDK 6. I guess I would need to build a custom Docker container. Cheers.