Part: modernize C++: return braced init list

src/Mod/Part/App/ShapeUpgrade/UnifySameDomainPyImp.cpp

@@ -108,7 +108,7 @@ PyObject* UnifySameDomainPy::initialize(PyObject *args, PyObject* kwds)
 // returns a string which represents the object e.g. when printed in python
 std::string UnifySameDomainPy::representation() const
 {
-    return std::string("<ShapeUpgrade_UnifySameDomain object>");
+    return {"<ShapeUpgrade_UnifySameDomain object>"};
 }
 
 PyObject* UnifySameDomainPy::allowInternalEdges(PyObject *args)