autoUpdate in config.json is ignored

### Describe the bug

I think starting with 1.0.4 the auto-update setting in config.json is no longer working.

### Affected version

1.0.4

### Steps to reproduce the behavior

1. start with 1.0.3
2. update config.json to have
"auto_update": false,
"autoUpdate": false,
3. start copilot version stays at 1.0.3
4. manually update to 1.0.4
5. start copilot and version is automatically updated latest

### Expected behavior

version stays at specific version

### Additional context

windows
x86_64
Windows Terminal

the --no-auto-update still works
the COPILOT_AUTO_UPDATE environment variable set to false still works

Start with the config.json handling for auto_update and autoUpdate, then compare it with the working --no-auto-update flag and COPILOT_AUTO_UPDATE environment variable behavior. Reproduce the 1.0.3-to-1.0.4 upgrade on Windows and verify that setting the configuration to false prevents automatic updates.

Written by the indexing model from the issue text.