BUG - handle http 404's in control property editor

[longieirl]

Description

Closing VSCode causes errors if changes are done in CPE.

Steps to Reproduce

1. Create ADP in VSCode
2. Open CPE
3. Close VSCode which probably also closes the server on which CPE is running
4. Do a change in CPE and save it

Expected results

In this instance, the server is no longer running and CPE should handle known exceptions i.e http 404 and give the user a better error message.

Actual results

Error is shown to the user showing exception around fetching service.

Screenshots

Version/Components/Environment

Add any other context about the problem here OS:

• [x] Mac OS
• [ ] Windows
• [ ] Other

Root Cause Analysis

Problem

{describe the problem}

Fix

{describe the fix}

Why was it missed

{Some explanation why this issue might have been missed during normal development/testing cycle}

How can we avoid this

{if we don’t want to see this type of issues anymore what we should do to prevent}