SqlClient: Allow |DataDirectory| macro in AttachDBFilename

[bricelam]

Now that .NET Standard 2.0 includes AppDomain.GetData, there shouldn't be anything blocking the implementation to expand the |DataDirectory| substitution string in the AttachDBFilename value of the connection string.

[divega]

As recently announced in the .NET Blog, focus on new SqlClient features an improvements is moving to the new Microsoft.Data.SqlClient package. For this reason, we are moving this issue to the new repo at https://github.com/dotnet/SqlClient. We will still use https://github.com/dotnet/corefx to track issues on other providers like System.Data.Odbc and System.Data.OleDB, and general ADO.NET and .NET data access issues.

[divega]

FYI: Customer porting application from .NET Framework hit this limitation: dotnet/efcore#17723.

[SidShaytay]

We're facing this on some of our demo applications after we made them compatible with the recent EF 6.3 release + .NET Core 3.0.

[Wraith2]

@ErikEJ has a PR for this at #284 which looks reasonable it just needs a bit of a push from the MS side i think

[ErikEJ]

Yes, it is awaiting review from @saurabh500

[cheenamalhotra]

Closing as #284 has been merged and fix will be available in v1.1.0