chore(telco errors): add 4785 error code

[ajohn25]

Description

This updates the list of telco errors to add 4785s

Motivation and Context

This error code was seen in production for the first time recently

How Has This Been Tested?

N/A

Screenshots (if appropriate):

Documentation Changes

Checklist:

• [ ] My change requires a change to the documentation.
• [ ] I have included updates for the documentation accordingly.