Bump Microsoft.NET.Test.Sdk in /Cake.PathTildeHelper.Tests (#21)

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 15.8.0-preview-20180610-02 to 17.0.0.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](microsoft/vstest@v15.8.0-preview-20180610-02...v17.0.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

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

Cake.PathTildeHelper.Tests/Cake.PathTildeHelper.Tests.csproj

@@ -8,7 +8,7 @@
   <ItemGroup>
     <PackageReference Include="Cake.Core" Version="2.0.0" />
     <PackageReference Include="Cake.Testing" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.8.0-preview-20180610-02" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
     <PackageReference Include="Moq" Version="4.16.1" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />