Fix email unsubscribe link for mobile

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I received an email today from GitHub with a notification from one of the 1,000+ things I have subscriptions for.

The email has an unsubscribe link:

https://github.com/notifications/unsubscribe-auth/AAC5JZ3G63HKNVAST4BXYZ32LDZ2VAVCNFSM6AAAAABVCUYGSSVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTCOBWGY2DQMY

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Here is my experience with that link:

1. I'm in bed on my iPhone.
   • This phone has GitHub application installed and logged in with the account that is relevant to this notification/email.
   • This phone is running iOS 18 (latest version ✅) and uses "lockdown mode" (that's an acceptable best practice ✅).
2. I open Proton email app to read this email.
3. I click unsubscribe (that link up top).
4. The phone navigates to Safari, showing a GitHub login page.

At this point I cannot proceed. I don't memorize my GitHub password (that's best practice ✅). I don't walk around with a password book on my phone (that's an acceptable practice ✅). And even if I did, I do not want to use Safari to login to GitHub (that's an acceptable practice ✅). And even if I did login, I would be logged out soon because I use private mode in Safari (that's an acceptable practice ✅).

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Instead I am hoping and expecting that after clicking the link, no login is required and I am immediately unsubscribed from that thread.

Or alternatively (and not as good), there is a link at the top of the page to "open this page in GitHub App" and then that clicks over and unsubscribes me without further effort.