[Infra] Remove redundant item (#6330)

Co-authored-by: Rajkumar Rangaraj <[email protected]>

Author: martincostello

build/Common.prod.props

@@ -36,13 +36,6 @@
     <ContinuousIntegrationBuild Condition="'$(Deterministic)'=='true'">true</ContinuousIntegrationBuild>
   </PropertyGroup>
 
-  <ItemGroup>
-    <!-- Note: Disable net6.0 target for package validation because it has been
-    removed. It should be possible to remove this once a stable version has been
-    released to NuGet without net6.0. -->
-    <PackageValidationBaselineFrameworkToIgnore Include="net6.0" />
-  </ItemGroup>
-
   <ItemGroup>
     <PackageReference Include="MinVer" PrivateAssets="All" Condition="'$(IntegrationBuild)' != 'true'" />
     <PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="All" Condition="'$(IntegrationBuild)' != 'true'" />