Backport: Disallow redirection to the host when performing redirect_back

[roxanaopr]

Co-authored-by: Alexandru-Emil Lupu contact@alecslupu.ro

🎩 What? Why?

Backports the fix from #8296 to 0.25.

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[leio10]

@roxanaopr can you rebase or merge with the lasts commits on the branch to fix the broken test?