trunk/7029dbea3cf43a16b69110f760bfa27956930f24: Run clang-tidy with readability-container-contains (#179436)

C++20 provides a contains member function for all associative containers.

Prior to C++20, the common pattern to check if an element is a member of a

container was to either container.find(key) != container.end() or

container.count(key) > 0. This PR replaces those instances with contains.

All the changes were done by running clang-tidy with the

readability-container-contains check enabled.

PyTorch now supports C++20 #176662

Pull Request resolved: #179436

Approved by: https://github.com/Skylion007