Fix compatibility with .NET 5 SDK InternalsVisibleTo

Author: antonfirsov

src/Directory.Build.props

@@ -44,9 +44,9 @@
     <PackageReference Include="StyleCop.Analyzers" IsImplicitlyDefined="true"  />
 
     <!-- DynamicProxyGenAssembly2 is needed so Moq can use our internals -->
-    <InternalsVisibleTo Include="DynamicProxyGenAssembly2" PublicKey="0024000004800000940000000602000000240000525341310004000001000100c547cac37abd99c8db225ef2f6c8a3602f3b3606cc9891605d02baa56104f4cfc0734aa39b93bf7852f7d9266654753cc297e7d2edfe0bac1cdcf9f717241550e0a7b191195b7667bb4f64bcb8e2121380fd1d9d46ad2d92d2d15605093924cceaf74c4861eff62abf69b9291ed0a340e113be11e6a7d3113e92484cf7045cc7" />
-    <InternalsVisibleTo Include="SixLabors.ImageSharp.Tests"  PublicKey="$(SixLaborsPublicKey)" />
-    <InternalsVisibleTo Include="ImageSharp.Drawing.Benchmarks"  PublicKey="$(SixLaborsPublicKey)" />
+    <InternalsVisibleTo Include="DynamicProxyGenAssembly2" Key="0024000004800000940000000602000000240000525341310004000001000100c547cac37abd99c8db225ef2f6c8a3602f3b3606cc9891605d02baa56104f4cfc0734aa39b93bf7852f7d9266654753cc297e7d2edfe0bac1cdcf9f717241550e0a7b191195b7667bb4f64bcb8e2121380fd1d9d46ad2d92d2d15605093924cceaf74c4861eff62abf69b9291ed0a340e113be11e6a7d3113e92484cf7045cc7" />
+    <InternalsVisibleTo Include="SixLabors.ImageSharp.Tests"  Key="$(SixLaborsPublicKey)" />
+    <InternalsVisibleTo Include="ImageSharp.Drawing.Benchmarks"  Key="$(SixLaborsPublicKey)" />
   </ItemGroup>
 
 </Project>

src/Directory.Build.targets

@@ -46,10 +46,10 @@
           Condition="'$(Language)' == 'VB' or '$(Language)' == 'C#'"
           Inputs="$(MSBuildAllProjects)"
           Outputs="$(GeneratedInternalsVisibleToFile)">
-    <CreateItem Include="System.Runtime.CompilerServices.InternalsVisibleToAttribute" AdditionalMetadata="_Parameter1=%(InternalsVisibleTo.Identity)" Condition="'%(InternalsVisibleTo.PublicKey)' == ''">
+    <CreateItem Include="System.Runtime.CompilerServices.InternalsVisibleToAttribute" AdditionalMetadata="_Parameter1=%(InternalsVisibleTo.Identity)" Condition="'%(InternalsVisibleTo.Key)' == ''">
       <Output TaskParameter="Include" ItemName="InternalsVisibleToAttribute" />
     </CreateItem>
-    <CreateItem Include="System.Runtime.CompilerServices.InternalsVisibleToAttribute" AdditionalMetadata="_Parameter1=%(InternalsVisibleTo.Identity), PublicKey=%(InternalsVisibleTo.PublicKey)" Condition="'%(InternalsVisibleTo.PublicKey)' != ''">
+    <CreateItem Include="System.Runtime.CompilerServices.InternalsVisibleToAttribute" AdditionalMetadata="_Parameter1=%(InternalsVisibleTo.Identity), PublicKey=%(InternalsVisibleTo.Key)" Condition="'%(InternalsVisibleTo.Key)' != ''">
       <Output TaskParameter="Include" ItemName="InternalsVisibleToAttribute" />
     </CreateItem>