Switch from deprecated tbb::mutex to std::mutex

[mmdanggg2]

ReleaseNote

Compatibility (major, minor, patch, build): build
Jira ticket: na
Release Notes Comment:

Special Notes: Changes away from tbb::mutex to the std::mutex as it has been deprecated and removed in tbb 2021+

Look or Scene Setup Change: No

[kjeffery]

Thank you for the changes! We have been slowly replacing tbb mutexes with std mutexes, but we have not concentrated on doing so.

Below is a note to the MoonRay developer who integrates this change. I'm not necessarily asking you to modify your patch.

std::scoped_lock should be replaced with std::lock_guard.

• std::scoped_lock does not exist until C++17, and we are targeting C++14.
• std::scoped_lock is for deterministicly locking of multiple mutexes. While this code is valid (it works for zero or more mutexes), we would be better off spelling what we mean with a std::lock_guard.