circular_buffer: mark pop/erase noexcept
circular_buffer: mark pop/erase noexcept

As std::allocator_traits<Alloc>::destroy is noexcept.

Signed-off-by: Benny Halevy <23c997c90eb8537635e9392d48e7af1bf1b2ca22@scylladb.com>

avikivity/seastar,syuu1228/seastar,cloudius-systems/seastar,scylladb/seastar,dreamsxin/seastar,avikivity/seastar,cloudius-systems/seastar,scylladb/seastar,scylladb/seastar,cloudius-systems/seastar,avikivity/seastar,syuu1228/seastar,syuu1228/seastar,dreamsxin/seastar,dreamsxin/seastar