fix: Environment webhook update button not working

[novakzaballa]

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Changes

Fixed Environment Webhook update button not working by adding the type='submit' attirbute. It was probably accidentally removed during the redesign.

How did you test this code?

Manually:

1. Go to the "Environment Settings" option at the left menu panel
2. Click on the "Webhooks" tab
3. Create a new Webhook or skip this step if you already have a Webhook
4. Edit the Webhook
5. Make changes to the Webhook and save the changes by clicking the "Update Webhook" button
6. See that the changes are saved now and can be retrieved refreshing the page and following the same steps.

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Uffizzi Preview deployment-36265 was deleted.