EF Core 9 support

[ChrisJollyAU]

Opening this issue for any questions on the EF Core 9 support.

Work has begun and the master branch is now targeting EF Core 9 (dependent on preview 7).

EF Core 9 does work on .Net 8 so you can update the EF Core part without changing the .Net version.

Currently it is only available on the daily build feed with myget, with hopefully an alpha 1 on nuget before the end of the month