Use EF Core 5.0.0-rc.1 from nuget.org (#446)

Author: AlekseyMartynov

appveyor.yml

@@ -10,7 +10,7 @@ install:
   # TODO remove when .NET 5 is RTM
   - nuget update -self
   - ps: "wget https://dot.net/v1/dotnet-install.ps1 -o dotnet-install.ps1"
-  - ps: "& .\\dotnet-install.ps1 -Version 5.0.100-preview.8.20417.9 -InstallDir $env:ProgramFiles\\dotnet"
+  - ps: "& .\\dotnet-install.ps1 -Version 5.0.100-rc.1.20452.10 -InstallDir $env:ProgramFiles\\dotnet"
 
   - if defined RELEASE_KEY_SECRET (nuget install secure-file -ExcludeVersion -Verbosity quiet && secure-file\tools\secure-file -decrypt net\DevExtreme.AspNet.Data\release.snk.enc -secret %RELEASE_KEY_SECRET%)
   - nuget install -Verbosity quiet -ExcludeVersion -OutputDirectory . OpenCover

net/DevExtreme.AspNet.Data.Tests.EFCore5/DevExtreme.AspNet.Data.Tests.EFCore5.csproj

@@ -6,7 +6,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="5.0.0-rc.1.20426.1" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="5.0.0-rc.1.20451.13" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.7.0" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />

net/NuGet.Config

@@ -5,7 +5,5 @@
   </config>
   <packageSources>
     <add key="api.nuget.org" value="https://api.nuget.org/v3/index.json" />
-    <!-- TODO remove when .NET 5 is RTM -->
-    <add key="dotnet-nightly" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet5/nuget/v3/index.json" />
   </packageSources>
 </configuration>