Update default nginx archive keyring to latest from nginx.org

[Seldaek]

I ran this to update the file:

curl -fsSL https://nginx.org/keys/nginx_signing.key | gpg --dearmor -o nginx-archive-keyring.gpg

The current one in the repo has a certificate which is expired, so it fails to be set up:

gpg --dry-run --quiet --no-keyring --import --import-options import-show /usr/share/keyrings/nginx-archive-keyring.gpg
pub   rsa2048 2011-08-19 [SC] [expired: 2024-06-14]
      573BFD6B3D8FBC641079A6ABABF5BD827BD9BF62
uid                      nginx signing key <signing-key@nginx.com