⬆️ Bump RichardSzalay.MockHttp from 6.0.0 to 7.0.0

Bumps [RichardSzalay.MockHttp](https://github.com/richardszalay/mockhttp) from 6.0.0 to 7.0.0.
- [Release notes](https://github.com/richardszalay/mockhttp/releases)
- [Changelog](https://github.com/richardszalay/mockhttp/blob/master/CHANGELOG)
- [Commits](richardszalay/mockhttp@v6.0.0...v7.0.0)

---
updated-dependencies:
- dependency-name: RichardSzalay.MockHttp
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Percy.Tests/Percy.Tests.csproj

@@ -12,7 +12,7 @@
   <ItemGroup>
     <PackageReference Include="Faker.Net" Version="2.0.154" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.6.3" />
-    <PackageReference Include="RichardSzalay.MockHttp" Version="6.0.0" />
+    <PackageReference Include="RichardSzalay.MockHttp" Version="7.0.0" />
     <PackageReference Include="xunit" Version="2.5.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.5.0">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>