GH-3759 use java.version as the main variable to control both the source level version and the which java version we will target with our builds (release).
GH-3759 use java.version as the main variable to control both the source level version and the which java version we will target with our builds (release).

eclipse/rdf4j,eclipse/rdf4j,eclipse/rdf4j,eclipse/rdf4j,eclipse/rdf4j,eclipse/rdf4j