Support Gradle's isolated projects feature

[wilkinsona]

https://docs.gradle.org/current/userguide/isolated_projects.html

Experimenting with the feature today should that our ResolvableDependencies, used both for layered jars and for identifying GraalVM metadata , isn't compatible. gradle/gradle#31973 is tracking a change in Gradle will hopefully improve the situation.

Related, spring-gradle-plugins/dependency-management-plugin#380 is tracking a similar enhancement to the dependency management plugin. In addition to being blocked on the above Gradle issue, it's also blocked on gradle/gradle#25179.