build(deps): Bump Microsoft.EntityFrameworkCore.SqlServer (#239)

Bumps [Microsoft.EntityFrameworkCore.SqlServer](https://github.com/dotnet/efcore) from 8.0.8 to 9.0.0.
- [Release notes](https://github.com/dotnet/efcore/releases)
- [Commits](dotnet/efcore@v8.0.8...v9.0.0)

---
updated-dependencies:
- dependency-name: Microsoft.EntityFrameworkCore.SqlServer
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

GraphQLNetExample/GraphQLNetExample.csproj

@@ -16,7 +16,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="8.0.8" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="9.0.0" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="9.0.0">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>