attr: don't declare StructureDescription for IsGroupAsSemigroup

Author: james-d-mitchell

gap/attributes/attr.gd

@@ -53,7 +53,6 @@ DeclareAttribute("SmallestElementSemigroup", IsSemigroup);
 DeclareAttribute("LargestElementSemigroup", IsSemigroup);
 
 DeclareAttribute("StructureDescription", IsBrandtSemigroup);
-DeclareAttribute("StructureDescription", IsGroupAsSemigroup);
 DeclareAttribute("StructureDescriptionMaximalSubgroups",
                  IsSemigroup);
 DeclareAttribute("MaximalDClasses", IsSemigroup);

gap/attributes/attr.gi

@@ -396,7 +396,7 @@ end);
 
 # same method for ideals
 
-InstallMethod(StructureDescription, "for a group as semigroup",
+InstallOtherMethod(StructureDescription, "for a group as semigroup",
 [IsGroupAsSemigroup],
 function(S)
   if IsGroup(S) then