modernize C++: use bool literals

src/App/DocumentPyImp.cpp

@@ -614,7 +614,7 @@ PyObject* DocumentPy::getObject(PyObject *args)
         PyErr_SetString(PyExc_TypeError, "a string or integer is required");
         return nullptr;
     }
-    while (0);
+    while (false);
 
     if (obj)
         return obj->getPyObject();

src/App/Expression.cpp

@@ -2806,7 +2806,7 @@ void VariableExpression::addComponent(Component *c) {
             var << ObjectIdentifier::RangeComponent(l1,l2,l3);
             return;
         }
-    }while(0);
+    }while(false);
 
     Expression::addComponent(c);
 }