Add do_no_delete handy alias for empty/no-op deleter : ATLASRECTS-4956
Following !23634 (merged) it seems to be easier to add
a handy
template<typename T>
auto do_not_delete = [](T*){};
so as to be
- More clear to the reader what is going on
- Be a bit easier to spot these from a search (grep/lxr , what not)