fix: Update Webhook button not working

[novakzaballa]

Thanks for submitting a PR! Please check the boxes below:

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• I have filled in the "Changes" section below?
• I have filled in the "How did you test this code" section below?
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Changes

Add type = 'submit' to the offending button.

How did you test this code?

Tested manually against local dev env

1. Go to the "Manage" option at the top menu bar
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 try to save the changes by clicking the "Update Webhook" button
6. See that the data has been updated in both the FE and backend by reloading the page.

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