Update nuget packages.

Author: wo80

CSparse.Tests/CSparse.Tests.csproj

@@ -41,9 +41,9 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="NUnit" Version="3.13.3" />
-    <PackageReference Include="NUnit3TestAdapter" Version="4.4.2" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.5.0" />
+    <PackageReference Include="NUnit" Version="3.14.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
   </ItemGroup>
 
   <ItemGroup>

CSparse/CSparse.csproj

@@ -33,7 +33,7 @@ Changes in version 3.8.0:
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="System.Memory" Version="4.5.5" Condition="'$(TargetFramework)' == 'netstandard2.0'"/>
+    <PackageReference Include="System.Memory" Version="4.5.5" Condition="'$(TargetFramework)' == 'netstandard2.0'" />
   </ItemGroup>
 
   <ItemGroup>