Restore old PyEval_EvalCode() signature for older versions of PyPy (GH-4236)

Partially reverts https://github.com/cython/cython/commit/1027db04fb7c5bbfea2b9bcdfce0b1f384e26a93

Cython/Utility/Builtins.c

@@ -78,7 +78,7 @@ static PyObject* __Pyx_PyExec3(PyObject* o, PyObject* globals, PyObject* locals)
                 "code object passed to exec() may not contain free variables");
             goto bad;
         }
-        #if PY_VERSION_HEX < 0x030200B1
+        #if PY_VERSION_HEX < 0x030200B1 || (CYTHON_COMPILING_IN_PYPY && PYPY_VERSION_NUM < 0x07030400)
         result = PyEval_EvalCode((PyCodeObject *)o, globals, locals);
         #else
         result = PyEval_EvalCode(o, globals, locals);