Update WGL Core Test

[RobertBColton]

I've updated the test to try creating a real actual core context using the appropriate WGL extension. I am unsure and forget if epoxy_has_gl_extension can check for WGL extensions, so I could use some help with what to replace that with if needed.

[ebassi]

You should use epoxy_has_wgl_extension() to check for a WGL extension.

[RobertBColton]

Done!

[ebassi]

Thanks for your patience. This looks good to me; it would be great to have a Windows CI pipeline to verify it, but I think it's kind of complicated to do with the spotty GL support on Windows…

[RobertBColton]

I think there may be a small problem though because I now see that lighting is tested in here... but lighting is fixed-function pipeline and not in the 3.1 or newer contexts. You can get them with the compatibility context though. Not sure what is appropriate, to only try the lighting enable if the core context creation failed?