Bump GraphQL from 8.7.0 to 8.8.0

---
updated-dependencies:
- dependency-name: GraphQL
  dependency-version: 8.8.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

src/Directory.Packages.props

@@ -6,7 +6,7 @@
   <ItemGroup>
     <PackageVersion Include="FluentValidation" Version="12.1.0" />
     <PackageVersion Include="FluentValidation.DependencyInjectionExtensions" Version="12.1.0" />
-    <PackageVersion Include="GraphQL" Version="8.7.0" />
+    <PackageVersion Include="GraphQL" Version="8.8.0" />
     <PackageVersion Include="GraphQL.MicrosoftDI" Version="8.7.0" />
     <PackageVersion Include="GraphQL.Server.Transports.AspNetCore" Version="8.3.2" />
     <PackageVersion Include="GraphQL.Server.Ui.GraphiQL" Version="8.3.2" />