Icon downloaded from feed URL instead of site URL

[gabe565]

Hey!

I recently force refreshed some feeds and noticed that the feed icon is now downloaded based on the feed URL instead of the website URL. This was introduced by #2871 because the NewIconChecker now uses c.feed.FeedURL instead of c.feed.SiteURL:

v2/internal/reader/icon/checker.go

Line 37 in c6c71c5

iconFinder := NewIconFinder(requestBuilder, c.feed.FeedURL, c.feed.IconURL)

This is fine in most cases, but for any feeds that use an RSS generation service like RSS-Bridge, RSSHub, or one I built called Transsmute, the feed generator's icon will be downloaded instead of the actual website icon.

I wouldn't mind opening a PR to fix this, but I wasn't sure if the change was intended.