Bump org.openjfx.version from 11.0.2 to 15
Bump org.openjfx.version from 11.0.2 to 15

Bumps `org.openjfx.version` from 11.0.2 to 15.

Updates `javafx-controls` from 11.0.2 to 15

Updates `javafx-fxml` from 11.0.2 to 15

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
speedment/speedment,speedment/speedment