Use Activator.CreateInstance in CosmosGrainStorage when record does not exist (#9277)

Use Activator.CreateInstance in CosmosGrainStorage to support types with primary constructors

Author: egil

src/Azure/Orleans.Persistence.Cosmos/CosmosGrainStorage.cs

@@ -75,7 +75,7 @@ public async Task ReadStateAsync<T>(string grainType, GrainId grainId, IGrainSta
             }
             else
             {
-                grainState.State = ActivatorUtilities.CreateInstance<T>(_serviceProvider);
+                grainState.State = Activator.CreateInstance<T>();
                 grainState.RecordExists = false;
             }
 
@@ -86,7 +86,7 @@ public async Task ReadStateAsync<T>(string grainType, GrainId grainId, IGrainSta
             if (dce.StatusCode == HttpStatusCode.NotFound)
             {
                 // State is new, just activate a default and return
-                grainState.State = ActivatorUtilities.CreateInstance<T>(_serviceProvider);
+                grainState.State = Activator.CreateInstance<T>();
                 grainState.RecordExists = false;
                 return;
             }