fix: Use correct type filter for LocalDevelopmentUser (#1744)

<!--- Provide a general summary of your changes in the Title above -->

## Description

<!--- Describe your changes in detail -->

## Related Issue(s)

- #1743 

## Verification

- [ ] **Your** code builds clean without any errors or warnings
- [ ] Manual testing done (required)
- [ ] Relevant automated test added (if you find this hard, leave it and
we'll help out)

## Documentation

- [ ] Documentation is updated (either in `docs`-directory, Altinnpedia
or a separate linked PR in
[altinn-studio-docs.](https://github.com/Altinn/altinn-studio-docs), if
applicable)

src/Digdir.Domain.Dialogporten.WebApi/Common/Authorization/AuthorizationPolicy.cs

@@ -24,7 +24,7 @@ internal static class AuthorizationScope
     private static ReadOnlyCollection<string> GetAll() =>
         typeof(AuthorizationScope)
             .GetFields()
-            .Where(x => x.IsLiteral && !x.IsInitOnly && x.DeclaringType == typeof(string))
+            .Where(x => x.IsLiteral && !x.IsInitOnly && x.FieldType == typeof(string))
             .Select(x => (string)x.GetRawConstantValue()!)
             .ToList()
             .AsReadOnly();