Suppress warning C5205 on Windows

[chapulina]

Attempting a fix for #140.

I queued a couple of test runs, but even though win-windows_local.win8 was idle (which uses VS2019 v16.8.3), they all waited to run on win-windows_nuc.win10 (which uses VS2019 v16.4.3), so I couldn't confirm that the fix works. Both CI machines seem to have the same labels, I don't know why the jobs only wanted to run on win10...

CI apart, I wonder if suppressing the new warning is the correct thing to do. It feels like VS2019 is trying to tell us something and we don't want to listen 🙉

[chapulina]

I just noticed that the job for this PR is also queuing waiting to run on win10, so I think we won't get to confirm the fix until we force it to run on win8.

[caguero]

It looks like we have our own internal test that triggers this warning and the expectation is that IGN_UTILS_WARN_IGNORE__NON_VIRTUAL_DESTRUCTOR should suppress it. I don't know why we need it but suppress it seems to be the goal here. Maybe @mxgrey can clarify?

[mjcarroll]

The only place I believe that this is used (besides the test case) is in ign-plugin: https://github.com/ignitionrobotics/ign-plugin/blob/4a87904ac0b70385d8e5bb520e84ab11aa2eaba5/register/include/ignition/plugin/detail/Register.hh#L376-L382

[scpeters]

warning C5205 was added in Visual Studio 2019 version 16.5

• https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warnings-by-compiler-version?view=msvc-160#warnings-introduced-in-visual-studio-2019-version-165-compiler-version-1925286100