Tools: Target .NET 6 to improve compatibility with osx-arm64

Also adds a shim we can sign for win-arm64 and rolls ef.dll forward across major runtime versions.

Fixes #27787, fixes #27827

Author: bricelam

src/dotnet-ef/dotnet-ef.csproj

@@ -12,10 +12,10 @@ dotnet ef dbcontext scaffold
 dotnet ef database drop
 dotnet ef database update
     </Description>
-    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <TargetFramework>net6.0</TargetFramework>
     <OutputType>Exe</OutputType>
     <PackAsTool>true</PackAsTool>
-    <PackAsToolShimRuntimeIdentifiers>win-x64;win-x86</PackAsToolShimRuntimeIdentifiers>
+    <PackAsToolShimRuntimeIdentifiers>win-x64;win-x86;win-arm64</PackAsToolShimRuntimeIdentifiers>
     <!-- Because this project uses a custom nuspec, this is necessary to ensure the generated shims are in the publish directory. -->
     <PackagedShimOutputRootDirectory>$(OutDir)</PackagedShimOutputRootDirectory>
     <RootNamespace>Microsoft.EntityFrameworkCore.Tools</RootNamespace>

src/ef/ef.csproj

@@ -8,6 +8,7 @@
     <RootNamespace>Microsoft.EntityFrameworkCore.Tools</RootNamespace>
     <CheckEolTargetFramework>False</CheckEolTargetFramework>
     <CodeAnalysisRuleSet>$(MSBuildThisFileDirectory)..\..\rulesets\EFCore.noxmldocs.ruleset</CodeAnalysisRuleSet>
+    <RollForward>Major</RollForward>
   </PropertyGroup>
 
   <ItemGroup>