[Bug c++/118719] [14/15 regression] Spurious -Wc++20-extensions warning emitted when capturing a structured binding

[dangelog at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118719

--- Comment #2 from Giuseppe D'Angelo <dangelog at gmail dot com> ---
Sorry, I assumed that, since 14 accepted valid code without warnings, but 15
introduces a spurious warning, then it would classify as a 14->15 regression.
Please do amend the subject if that reasoning is wrong.