Update from System.Data.SqlClient to Microsoft.Data.SqlClient in v0.x

[janrybka]

Details in of update in discussion: https://github.com/eventflow/EventFlow/discussions/1022#discussion-6435423

PR contains minimal set of changes to make transfer to Microsoft.Data.SqlClient successful. Threat warning as errors caused problems for valnerable packages. I've updated only Newtonsoft.Json as this I could test. I didn't have any MongoDB or Owin project to test on, so these are now marked with "NoWarn" option. I could try to update those also, but in this case I'd go with Yurii's PR and update all.

[rasmus]

Nice and clean PR.

0.x builds aren't working (need help or time to get them up and running again), but I'll try to verify this manually to see if it can be merged.

[janrybka]

I've tried to get build.ps1 up, but I only got it to run by commenting out #module nuget:?package=Cake.DotNetTool.Module. Unfortunately, it hang on unit tests. I also didn't know how to knit it with GitHub workflow, so I gave up at the point.