Not able to remove the delay from flux script

Updating task by setting `offset` field to `0s` or to and empty string (not sure if it is supported) will result in error:
```
cannot update task without content
```

I am assuming that setting `offset` to `0s` should result in removing the `delay` option from flux script.

- Create a task with `delay` option.
- Request body:
```
{
"flux": "option task = {name:\"task_urdfc\", cron: \"* * * * *\", delay: 15s} from(bucket:\"read_from_b_query_params\") |> range(start: -1h)",
"orgID": "0376c42cfa80c000",
"status": "active"
}
```

- Update created above task with `offset` = `0s`
- Request body
```
{"offset": "0s"}
```

- Response:
```
{
"code": "internal error",
"error": "cannot update task without content",
"message": "failed to update task"
}
```