Fix: Remove PComplex specialization from PyComplexCheckExactNode.

According to CPython doc `PyComplex_CheckExact` should return true if the argument is
a PyComplexObject, but not if its a subtype of PyComplexObject. Accordingly, we shouldn't
return true for subtypes of PComplex.

Author: phoeinx

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/lib/PyComplexCheckExactNode.java

@@ -41,7 +41,6 @@
 package com.oracle.graal.python.lib;
 
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
-import com.oracle.graal.python.builtins.objects.complex.PComplex;
 import com.oracle.graal.python.nodes.object.IsBuiltinClassProfile;
 import com.oracle.truffle.api.dsl.Cached;
 import com.oracle.truffle.api.dsl.GenerateUncached;
@@ -55,11 +54,6 @@
 public abstract class PyComplexCheckExactNode extends Node {
     public abstract boolean execute(Object object);
 
-    @Specialization
-    static boolean doPComplex(PComplex pComplex) {
-        return true;
-    }
-
     @Specialization
     static boolean doGeneric(Object object,
                     @Cached IsBuiltinClassProfile isBuiltin) {