build: Remove global set of CLSCompliantAttribute

This was originally put in place in commit b0bbb23d3 (from 2021) to
silence analysis warnings. However, I observed no warnings so this must
have been corrected in dotnet since then.

Directory.Build.props

@@ -24,11 +24,4 @@
   <ItemGroup Condition="!$(ProjectName.EndsWith('.Tests'))">
     <InternalsVisibleTo Include="$(AssemblyName).Tests" />
   </ItemGroup>
-
-  <ItemGroup>
-    <!-- From https://github.com/dotnet/msbuild/pull/6285 -->
-    <AssemblyAttribute Include="System.CLSCompliantAttribute">
-      <_Parameter1>false</_Parameter1>
-    </AssemblyAttribute>
-  </ItemGroup>
 </Project>

tests/Directory.Build.props

@@ -44,6 +44,7 @@
   </ItemGroup>
 
   <ItemGroup>
+    <!-- From https://github.com/dotnet/msbuild/pull/6285 -->
     <AssemblyAttribute Include="NUnit.Framework.ParallelizableAttribute">
       <_Parameter1>NUnit.Framework.ParallelScope.All</_Parameter1>
       <_Parameter1_IsLiteral>true</_Parameter1_IsLiteral>