chore: Added systemlabel to search (#1238)

Added systemlabel to search

## Description


## Related Issue(s)

- #{issue number}

## Verification

- [x] **Your** code builds clean without any errors or warnings
- [x] 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)

Co-authored-by: Amund Myrbostad <amund.myrbostad@digdir.no>

docs/schema/V1/schema.verified.graphql

@@ -193,6 +193,7 @@ type SearchDialog {
   updatedAt: DateTime!
   dueAt: DateTime
   status: DialogStatus!
+  systemLabel: SystemLabel!
   latestActivity: Activity
   content: SearchContent!
   seenSinceLastUpdate: [SeenLog!]!

src/Digdir.Domain.Dialogporten.GraphQL/EndUser/SearchDialogs/ObjectTypes.cs

@@ -1,4 +1,5 @@
 using Digdir.Domain.Dialogporten.GraphQL.EndUser.Common;
+using Digdir.Domain.Dialogporten.GraphQL.EndUser.MutationTypes;
 
 namespace Digdir.Domain.Dialogporten.GraphQL.EndUser.SearchDialogs;
 
@@ -45,6 +46,8 @@ public sealed class SearchDialog
 
     public DialogStatus Status { get; set; }
 
+    public SystemLabel SystemLabel { get; set; }
+
     public Activity? LatestActivity { get; set; }
 
     public SearchContent Content { get; set; } = null!;