jextract: NFC Fix calling wrong function in the unittest (#887)

Author: AmrDeveloper

Samples/SwiftAndJavaJarFFMSampleLib/src/test/java/com/example/swift/MySwiftLibraryTest.java

@@ -74,7 +74,7 @@ void call_globalCallMeLongSupplier_noThrow() {
 
     @Test
     void call_globalCallMeDoubleSupplier_noThrow() {
-        double result = MySwiftLibrary.globalCallMeBooleanSupplier(() -> { return 2.0; });
+        double result = MySwiftLibrary.globalCallMeDoubleSupplier(() -> { return 2.0; });
         assertEquals(2.0, result);
     }