Bump GraphQL.Server.Ui.Playground from 5.0.0 to 5.0.1 (#134)

Bumps [GraphQL.Server.Ui.Playground](https://github.com/graphql-dotnet/server) from 5.0.0 to 5.0.1.
- [Release notes](https://github.com/graphql-dotnet/server/releases)
- [Commits](graphql-dotnet/server@5.0.0...5.0.1)

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

src/Harness/Harness.csproj

@@ -11,7 +11,7 @@
   <ItemGroup>
     <PackageReference Include="GraphQL.Server.Transports.AspNetCore.SystemTextJson" Version="5.0.0" />
     <PackageReference Include="GraphQL.Server.Ui.GraphiQL" Version="5.0.1" />
-    <PackageReference Include="GraphQL.Server.Ui.Playground" Version="5.0.0" />
+    <PackageReference Include="GraphQL.Server.Ui.Playground" Version="5.0.1" />
     <PackageReference Include="GraphQL.Server.Transports.AspNetCore" Version="5.0.0" />
   </ItemGroup>