Remove duplicate GAP wrapper (#4364)

This triggered Julia WARNINGS about method definitions being overwritten.

Author: fingolfin

src/GAP/wrappers.jl

@@ -312,7 +312,6 @@ GAP.@wrap OnTuples(x::GapObj, y::GapObj)::GapObj
 GAP.@wrap Order(x::Any)::GapInt
 GAP.@wrap OrthogonalComponents(x::GapObj, y::GapObj, z::GapInt)::GapObj
 GAP.@wrap PcElementByExponentsNC(x::GapObj, y::GapObj)::GapObj
-GAP.@wrap PcpElementByExponentsNC(x::GapObj, y::GapObj)::GapObj
 GAP.@wrap Pcgs(x::GapObj)::GapObj
 GAP.@wrap PcpElementByExponentsNC(x::GapObj, y::GapObj)::GapObj
 GAP.@wrap PcpGroupByCollectorNC(x::GapObj)::GapObj