Provider derived class destruction uses static binding instead of dynamic binding

[yblake]

VS 2022 complains with warning C5205 because Provider abstract class defines a non virtual destructor, which may lead to undefined behaviour as objects destruction in ndfrmwrk.cpp use static binding instead of dynamic binding.

Suggested correction :

• To ensure all destructors are called, nedd to change ~Provider(void); to virtual ~Provider(void); in ndprov.h
• Should also comment (or delete) ~NdV1Provider(); and ~NdProvider(); definitions, since these derived constructors are not implemented.
• Finally, suppress AdditionalOptions /Wv:18 added by PR ADD AdditionalOptions Wv:18

[yblake]

Same potential memory leak in test abstract classes, that may be improperly destroyed. In ndtestutil.h, change destructors from ~NdTestBase(); to virtual ~NdTestBase(); , and ~NdTestServerBase(); to virtual ~NdTestServerBase();.

[MrDavid949]

Hi, this bug has been fixed in my fork:
https://github.com/MrDavid949/NetworkDirect ...This fork also allows building with Visual Studio 2022.