Cascade project configuration changes to child projects

[shawmanz32na]

Given a Maven project with a parent POM and two child modules and VS Code configured with "java.configuration.updateBuildConfiguration": "automatic", it'd be awesome if changes to the parent POM would cause the parent project AND the child modules' projects to be updated. Currently, changes to the parent POM cause only the parent project to be updated, and users must run the Java: Update java configuration command on each of the child projects before the project changes are applied.

This relates to #621, but differs in that this speaks about automatically applying the changes to child projects, while #621 speaks more to specifying which project(s) are to be updated when the Java: Update java configuration command is run from outside the context of a build file.