Update attach.ts to fix "clientOS" configuration

[cute-cirno]

Fix "clientOS" options

My debugger works in VS Code versions <=1.71.2. In higher versions, it can attach but fails to hit breakpoints. By comparing the logs, I found that in higher versions of VS Code, the option "WindowsClient" was missing during the debugger initialization. I manually added it, and the breakpoints were successfully hit.

So, I reviewed the code of this plugin and found that the options "WindowsClient" and "UnixClient" were defined but not set according to "clientOS".

[karthiknadig]

This is a bug in debugpy,

@rchiodo debugpy config handler should read this from clientOS. debugOptions is a deprecated field.

This was intentionally removed as debugpy added support to read this config setting.

removal PR: https://github.com/microsoft/vscode-python/pull/20805/files
Debugpy code where clientOS is read: https://github.com/microsoft/debugpy/blob/fb0b06cab161478db95420c5bfb485c39d508f62/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_json_debug_options.py#L98-L99

[rchiodo]

It seems that debugpy is reading this value. Perhaps @cute-cirno has their own version of debugpy?

The value is read here:
https://github.com/microsoft/debugpy/blob/fb0b06cab161478db95420c5bfb485c39d508f62/src/debugpy/_vendored/pydevd/_pydevd_bundle/pydevd_process_net_command_json.py#L399

[cute-cirno]

Oh! I understand. Since I am using a very old version of debugpy and cannot upgrade it, the clientOS configuration option has no effect when I use the new Python extension for debugging.