Bump xunit from 2.6.6 to 2.7.0

Bumps [xunit](https://github.com/xunit/xunit) from 2.6.6 to 2.7.0.
- [Commits](xunit/xunit@2.6.6...2.7.0)

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

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

Author: dependabot[bot]

src/AdoNet.Specification.Tests/AdoNet.Specification.Tests.csproj

@@ -33,8 +33,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="xunit" Version="2.6.6" />
-    <PackageReference Include="xunit.extensibility.execution" Version="2.6.6" />
+    <PackageReference Include="xunit" Version="2.7.0" />
+    <PackageReference Include="xunit.extensibility.execution" Version="2.7.0" />
     <PackageReference Include="Xunit.SkippableFact" Version="1.4.13" />
   </ItemGroup>