Filter List Manager ignores Custom proxy settings

[AlexandrPkhm]

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AdGuard version

7.20

Issue Details

Filter List Manager does not use proxy defined in System settings to retrieve Filter updates

Steps to reproduce:

1. Start any HTTPS proxy (Mitmproxy)
2. Open AdGuard → Settings → Network → Proxy Settings → Manual proxy configuration and enter your proxy data
3. Request filter updates and check the proxy logs

Expected Behavior

AdGuard uses a proxy specified in Settings for Filter updates. Requests are registered in proxy logs.

Actual Behavior

Requests are not registered in the proxy logs.