Fix android example test exclusive flag (com-lihaoyi#4449)

The earlier PR defined `ExampleCrossModuleAndroid` but didn't use it

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Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

Author: 2 people

example/package.mill

@@ -26,9 +26,10 @@ object `package` extends RootModule with Module {
     .collect { case m: ExampleCrossModule => m }
 
   object android extends Module {
-    object javalib extends Cross[ExampleCrossModuleJava](build.listIn(millSourcePath / "javalib"))
+    object javalib
+        extends Cross[ExampleCrossModuleAndroid](build.listIn(millSourcePath / "javalib"))
     object kotlinlib
-        extends Cross[ExampleCrossModuleJava](build.listIn(millSourcePath / "kotlinlib"))
+        extends Cross[ExampleCrossModuleAndroid](build.listIn(millSourcePath / "kotlinlib"))
   }
   object javalib extends Module {