Update NUnit to latest version

Author: jcoliz

tests/ExcelFinancialFunctions.Tests/ExcelFinancialFunctions.Tests.fsproj

@@ -17,7 +17,7 @@
   <ItemGroup>
     <PackageReference Include="FsCheck" Version="2.16.4" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.1.0" />
-    <PackageReference Include="NUnit" Version="3.13.2" />
+    <PackageReference Include="NUnit" Version="3.13.3" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.2.1" />
     <PackageReference Include="coverlet.collector" Version="3.1.2">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>