CachedValue : Add noexcept to move operations
Following similar changes to :
- https://gitlab.cern.ch/atlas/athena/-/blob/master/Control/CxxUtils/CxxUtils/CachedUniquePtr.h
- https://gitlab.cern.ch/atlas/athena/-/blob/master/Control/CxxUtils/CxxUtils/CachedPointer.h
Make move operation noexcept
https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c66-make-move-operations-noexcept (defaulting does it automatically if possible, but needs the member moves to be noexcept , so this is for classes having cacheValue members).