make a word not generic, remove unit test for unimplemented feature

core/classes/tuple/parser/parser-tests.factor

@@ -150,9 +150,3 @@ TUPLE: parsing-corner-case x ;
     TUPLE: book { name initial-quot: [ "Lord of the " "Rings" append ] } ;">
     eval( -- )
 ] unit-test
-
-[ ] [
-    <" IN: classes.tuple.tests
-    TUPLE: monster { hp virtual } ;">
-    eval( -- )
-] unit-test

core/classes/tuple/tuple.factor

@@ -75,9 +75,7 @@ PRIVATE>
 : tuple-slots ( tuple -- seq )
     prepare-tuple>array drop copy-tuple-slots ;
 
-GENERIC: slots>tuple ( seq class -- tuple )
-
-M: tuple-class slots>tuple
+: slots>tuple ( seq class -- tuple )
     check-slots pad-slots
     tuple-layout <tuple> [
         [ tuple-size ]