Send as3 webhook via proxy

[mmuser03]

Is your feature request related to a problem? Please describe.

I configured a webhook via the https://{{host}}/mgmt/shared/appsvcs/settings endpoint and deployed a as3 to test. But nothing happened and I found the following entry in the restnoded.log

Tue, 17 Sep 2024 09:20:17 GMT - severe: [appsvcs] {"message":"POST https://webexapis.com/v1/webhooks/incoming/************************* Sending response to webhook failed (getaddrinfo ENOTFOUND webexapis.com webexapis.com:443)","level":"error"}

The webhook can only work when using our companys proxy to access the external webex endpoint. (Tested via curl from the same machine)

Describe the solution you'd like

A way to configure a proxy for the webhook