Move from boost::optional to std::optional

[peterfpeterson]

Description of work

Since std::optional is part of C++17, move the easy parts of mantid to use it. This does not modify Framework/Geometry/inc/MantidGeometry/Crystal/MatrixVectorPairParser.h or the ISISReflectometryGUI code.

Framework/API/inc/MantidAPI/AlgorithmProperties.h was made to support both std::optional and boost::optional to handle the ISISReflectometryGUI not being moved.

Purpose of work

The preference for implementation (in order) is generally:

1. compiler feature
2. existing dependency / write in the repository
3. new dependency

This is moving from boost to c++17

Refs #37875.

Further detail of work

To test:

This is a refactor and does not require anything other than the changes make sense and the tests continue to pass

This does not require release notes because it is an internal change to modernize the code.

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