build: Upgrade AutoFixture to 5.0.0-preview0011

This is to eliminate the NUnit version 3 warnings; covered here:
https://github.com/AutoFixture/AutoFixture/issues/1418

Directory.Packages.props

@@ -39,9 +39,9 @@
   <ItemGroup>
     <PackageVersion Include="AgileObjects.ReadableExpressions" Version="4.1.1" />
     <PackageVersion Include="AutofacContrib.NSubstitute" Version="7.0.0" />
-    <PackageVersion Include="AutoFixture" Version="4.18.1" />
-    <PackageVersion Include="AutoFixture.AutoNSubstitute" Version="4.18.1" />
-    <PackageVersion Include="AutoFixture.NUnit3" Version="4.18.1" />
+    <PackageVersion Include="AutoFixture" Version="5.0.0-preview0011" />
+    <PackageVersion Include="AutoFixture.AutoNSubstitute" Version="5.0.0-preview0011" />
+    <PackageVersion Include="AutoFixture.NUnit4" Version="5.0.0-preview0011" />
     <PackageVersion Include="coverlet.collector" Version="6.0.2" />
     <PackageVersion Include="FluentAssertions" Version="6.12.0" />
     <PackageVersion Include="FluentAssertions.Analyzers" Version="0.31.0" />

tests/Directory.Build.props

@@ -12,7 +12,7 @@
     <PackageReference Include="AutofacContrib.NSubstitute" PrivateAssets="all" />
     <PackageReference Include="AutoFixture" PrivateAssets="all" />
     <PackageReference Include="AutoFixture.AutoNSubstitute" PrivateAssets="all" />
-    <PackageReference Include="AutoFixture.NUnit3" PrivateAssets="all" />
+    <PackageReference Include="AutoFixture.NUnit4" PrivateAssets="all" />
     <PackageReference Include="coverlet.collector" PrivateAssets="all" />
     <PackageReference Include="FluentAssertions" PrivateAssets="all" />
     <PackageReference Include="FluentAssertions.Analyzers" PrivateAssets="all" />
@@ -31,7 +31,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Using Include="AutoFixture.NUnit3" />
+    <Using Include="AutoFixture.NUnit4" />
     <Using Include="FluentAssertions" />
     <Using Include="NSubstitute" />
     <Using Include="NUnit.Framework" />