Fix copy-pasta.

Author: jnthn

src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/NativeRef.java

@@ -32,10 +32,10 @@ public SixModelObject allocate(ThreadContext tc, STable st) {
                         obj = new NativeRefInstanceIntLex();
                         break;
                     case StorageSpec.BP_NUM:
-                        obj = new NativeRefInstanceIntLex();
+                        obj = new NativeRefInstanceNumLex();
                         break;
                     case StorageSpec.BP_STR:
-                        obj = new NativeRefInstanceIntLex();
+                        obj = new NativeRefInstanceStrLex();
                         break;
                     default:
                         throw ExceptionHandling.dieInternal(tc,