[extractor/AbemaTV] Fix adding proxy parameters (fixes #8036)

[SevenLives]

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Fixes #8036

• Fix the issue of downloading failure at AbemaTV site due to the addition of non-standard proxy parameters.

Template

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Copilot Summary

🤖 Generated by Copilot at 02c3220

Summary

🧹🛠️📺

Fix proxy issues with AbemaTV extractor by using clean_proxies function. Update add_opener to apply this function to ydl.proxies.

Oh we're the crew of the Python ship, and we sail the web so free
We use ydl to download our shows, from AbemaTV
But we need to clean our proxies well, or the license won't come through
So we import clean_proxies now, and we call it in add_opener too

Walkthrough

• Import and use clean_proxies function to remove proxy headers from requests to AbemaTV license server (link, link)
• Update add_opener function to pass cleaned proxies to rh._get_instance method (link)