Sync enum example with its (original?) intent

... At least as far as I understood it.
Also, while here, drop unneeded parentheses in enum construction.

doc/Language/typesystem.pod6

@@ -792,10 +792,10 @@ that have been defined. All of them turn the values into C<Str>, which may not
 be desirable. By treating the enum as a package, we can get a list of types for
 the keys.
 
-    enum E(<one two>);
+    enum E <one two>;
     my @keys = E::.values;
-    say @keys.map: *.enums;
-    # OUTPUT: «(Map.new((one => 0, two => 1)) Map.new((one => 0, two => 1)))␤»
+    say @keys.map: *.perl;
+    # OUTPUT: «(E::one E::two)␤»
 
 With the use of B<()> parentheses, an enum can be defined using any
 arbitrary dynamically defined list. The list should consist of Pair