[WIP] Porting SqlDataSourceEnumerator from System.Data.Sql

[Kaur-Parminder]

This PR ports feature from System.Data.Sql for SqlDataSourceEnumerator.GetDataSources Method . SNI changes will be available with next preview release.

• Added SqlDataSourceEnumerator Public API methods
• Added unit tests for feature.
• endpoints for Native SNI

[Wraith2]

Is there going to be a managed implementation provided for the non-windows builds? If so would it be possible to use that one on all builds and avoid introducing new code that perpetuates the managed vs native sni.

[Kaur-Parminder]

Is there going to be a managed implementation provided for the non-windows builds?
Yes
If so would it be possible to use that one on all builds and avoid introducing new code that perpetuates the managed vs native sni.
I will be getting feedback from team on both implementations and discuss internally, How we want to manage it moving forward. It can be with AppContext Switch, not sure. I will keep you posted here.

[Wraith2]

Ok. As long as it's a consideration. I can see that it might be a good first step to use the native implementation so the results can be tested. In the long term the plan to move this library to a managed only implementation would mean that it's important to have a high quality managed implementation.

[Kaur-Parminder]

I am closing this PR as all the work done here is moved to #1430