Bump NuGet.CommandLine from 6.0.0 to 6.2.1

Bumps [NuGet.CommandLine](https://github.com/NuGet/NuGet.Client) from 6.0.0 to 6.2.1.
- [Release notes](https://github.com/NuGet/NuGet.Client/releases)
- [Commits](https://github.com/NuGet/NuGet.Client/commits)

---
updated-dependencies:
- dependency-name: NuGet.CommandLine
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

_build/_build.csproj

@@ -11,7 +11,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="NuGet.CommandLine" Version="6.0.0">
+    <PackageReference Include="NuGet.CommandLine" Version="6.2.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>