Tried your approach, created a Webhook with order.updated as an action.

Now ordered the product. And did the following
The status is changed using the following buttons.

But the website was not launched at all.
Then I went into the appropriate order and added some custom field value and clicked on the save order.

Then checked the Webhook log. Yes for this above action the webhook is launched.

Now I tried to change the status of the order on the order edit page itself.
Here it changed from processing status to retention status and kept order. (Status processing was set earlier when trying to update the status from the order list dashboard itself.)

Checked webhook again for the same thing. Yes, and now webhook had another trigger registered in it.

Finally, I came to the conclusion that this order.updated action is triggered when any changes are made and saved, viewing the editing page of one order.
A Collaborator suggested using action.woocommerce_order_status_changed instead.
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