build(deps): bump NuGet.Protocol from 6.5.1 to 6.7.0 (#94)

Bumps [NuGet.Protocol](https://github.com/NuGet/NuGet.Client) from 6.5.1 to 6.7.0.
- [Release notes](https://github.com/NuGet/NuGet.Client/releases)
- [Commits](https://github.com/NuGet/NuGet.Client/commits)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/ReactiveMarbles.NuGet.Helpers/ReactiveMarbles.NuGet.Helpers.csproj

@@ -8,7 +8,7 @@
 
 	<ItemGroup>
 		<PackageReference Include="NuGet.LibraryModel" Version="6.5.0" />
-		<PackageReference Include="NuGet.Protocol" Version="6.5.1" />
+		<PackageReference Include="NuGet.Protocol" Version="6.7.0" />
 	</ItemGroup>
 
 </Project>