[java] add a test case for #9574 (#9575)

tests/misc/java/projects/Issue9574/Main.hx

@@ -0,0 +1,3 @@
+function main() {
+	Test.dollarArgName(0);
+}

tests/misc/java/projects/Issue9574/Test.java

@@ -0,0 +1,3 @@
+public class Test {
+	public static void dollarArgName(int $dollar) {}
+}

tests/misc/java/projects/Issue9574/compile.hxml

@@ -0,0 +1,10 @@
+--cmd javac -d bin Test.java -g
+--cmd cd bin
+--cmd jar cf test.jar Test.class
+--cmd cd ..
+
+--next
+
+--main Main
+--java-lib-extern bin/test.jar
+--jvm bin/main.jar