Send a notification to discord using webhooks

### Description of the issue
A user wants to receive webhook notifications whenever there are updates to a task they are subscribed to.

### Steps to reproduce
1. The user creates a new task in the task board.
2. The user enters the webhook URL in the designated field for notifications.
3. The user adds other users as subscribers to the task.
4. An update is made to the task (for example, change of status, assignment to a new user, attach a file).

### Expected behaviour
- A webhook notification is sent to the URL specified by the task creator user.
- The notification should include relevant information about the task update, such as the task name, the change made, the user who made the change, and the date/time of the update.

### Actual behaviour
Currently, the task board application does not have functionality to send webhook notifications. Task updates are only reflected in the application's user interface.

### Possible solutions
- Develop a new plugin that integrates with the existing task board functionality.
- The plugin should allow users to:
- Configure the webhook URL for each individual task.
- Select the task events that will trigger a webhook notification (for example, status change, user assignment, etc.).
- The plugin should use the Huly HTTP library to send JSON notifications to the specified webhook URL.
- The JSON notification should contain relevant information about the task update.

Start by locating the task board update flow and the Huly HTTP library mentioned in the issue. Determine how task-specific webhook URLs, subscribed events, and update details are represented, then verify that notifications contain the task name, change, actor, and timestamp and are sent for the selected events.

Written by the indexing model from the issue text.