[Bug libstdc++/125228] Avoid using assert in libstdc++

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125228

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Yes, that file should not be including <cassert> at all (I incorrectly assumed
it wasn't, and that only the ryu headers included assert.h)