Bump Microsoft.NET.Test.Sdk from 18.3.0 to 18.4.0 (#1995)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]

UnitTests/UnitTests.csproj

@@ -24,7 +24,7 @@
 
   <ItemGroup>
     <PackageReference Include="AltCover" Version="9.0.102" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.4.0" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.4" />
     <PackageReference Include="nunit" Version="4.5.1" />
     <PackageReference Include="NUnit.Analyzers" Version="4.12.0">