[tests] remove leftover compile-as3.hxml

tests/unit/compile-as3.hxml

@@ -1,9 +0,0 @@
--cmd compc -output native_swf/lib.swc -include-sources native_swf/
-
---next
-
-compile-each.hxml
---main unit.TestMain
--as3 bin/as3
--swf-lib native_swf/lib.swc
--cmd mxmlc -include-libraries=native_swf/lib.swc -static-link-runtime-shared-libraries=true -debug bin/as3/__main__.as --output bin/unit9_as3.swf