Correct the log message for IAsyncEnumerable

[pranavkm]

Makes the logs more accurate:

dbug: Microsoft.AspNetCore.Mvc.Infrastructure.ObjectResultExecutor[1]
      Buffering IAsyncEnumerable instance of type 'Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryable`1[[validation.Topping, validation, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]'.

...

info: Microsoft.AspNetCore.Mvc.Infrastructure.ObjectResultExecutor[1]
      Executing ObjectResult, writing value of type 'System.Collections.Generic.List`1[[validation.Topping, validation, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]'.