Only root Maven projects could be unlinked, and jdtls imports an aggregator with all of its modules whatever java.import.exclusions say. A module of a reactor can now be unlinked from the Maven tool window; when one is, jdtls gets initializationOptions.projectConfigurations listing the linked POMs except the aggregators above the unlinked module (plus the Gradle build file if there is one), and a Maven sync only names the POMs jdtls imported. Unlinking whole roots keeps using exclusions.
Fixes#767