JavaAppLauncher doesn't pass multiple JVM options with the same key

ADDITIONAL SYSTEM INFORMATION :
java version "10.0.2" 2018-07-17
Java(TM) SE Runtime Environment 18.3 (build 10.0.2+13)
Java HotSpot(TM) 64-Bit Server VM 18.3 (build 10.0.2+13, mixed mode)

A DESCRIPTION OF THE PROBLEM :
`javapackager -deploy` sets multiple JVM options with the same key correctly, but the deployed launcher doesn't pass the options to the JVM correctly.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javac Main.java
javapackager -createjar -appclass Main -srcdir . -srcfiles Main.class -outdir jar -outfile example
javapackager -deploy -native image -outdir package -outfile example -appclass Main -srcdir jar -BjvmOptions=--add-opens=java.base/sun.nio.ch=ALL-UNNAMED -BjvmOptions=--add-opens=java.base/java.io=ALL-UNNAMED
Run package\Main\Main.exe

`javapackager -deploy` sets the two --add-opens options to package/Main/app/Main.cfg as expected.
[JVMOptions]
--add-opens=java.base/sun.nio.ch=ALL-UNNAMED
--add-opens=java.base/java.io=ALL-UNNAMED

But the Main.exe passes two same options to the JVM.
--add-opens=java.base/sun.nio.ch=ALL-UNNAMED
--add-opens=java.base/sun.nio.ch=ALL-UNNAMED

I confirmed this using VisualVM.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The Main.exe passes two different --add-opens options to the JVM.
--add-opens=java.base/sun.nio.ch=ALL-UNNAMED
--add-opens=java.base/java.io=ALL-UNNAMED
ACTUAL -
The Main.exe passes two same --add-opens options to the JVM.
--add-opens=java.base/sun.nio.ch=ALL-UNNAMED
--add-opens=java.base/sun.nio.ch=ALL-UNNAMED

---------- BEGIN SOURCE ----------
import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.stage.Stage;

public class Main extends Application {

    public static void main(String[] args) {
        Application.launch(args);
    }

    @Override
    public void start(Stage stage) {
        final Scene scene = new Scene(new Group(), 640, 480);
        stage.setScene(scene);
        stage.show();
    }
}
---------- END SOURCE ----------

FREQUENCY : always