Migrate to NegotiateAuthentication for GSSAPI authentication on .NET 7

[filipnavara]

Is your feature request related to a problem? Please describe.

Currently SqlClient uses custom interop to call into the System.Net.Security.Native interop on .NET Core / 5 / 6. This is an internal API that is not intended for public consumption. It was previously broken on at least one occasion (dotnet/runtime@e334603). On .NET 7 a new public NegotiateAuthentication API was added (dotnet/runtime#69920, dotnet/runtime#70909) to address the scenarios. Furthermore, the NegotiateAuthentication is supported on platforms like Android where the native GSSAPI shim is not available.

Describe the solution you'd like

Remove any interop dependency on System.Net.Security.Native for .NET 7 and newer, migrate to NegotiateAuthentication API instead.

[JRahnama]

@filipnavara thanks for bringing this up. We would love to do so, but there was no proper solution to address the issue. We have some conversations with related teams. We probably wait till Netcoreapp 3.1 is out of support by the end of this year and Net7 GA is released.

[filipnavara]

Presumably fixed by #2063.