22.0-cleanup-TrkGeometrySurfaces (2)

Work undertaken in context of ATLASRECTS-6307, addressing the SlidingDiscSurface. Replacing pointer members with values and adjusting constructors and clients accordingly to avoid use of 'new' in clients. Finally this enabled the omission of default c'tor, assignment, copy c'tor and d'tor (compiler does the work). Small additional cleanups performed, removing commented code, ensuring cmath std:: functions are used, tidying 'include' statements.