Snippets for xapian-bindings 1.4.31 from Nix aarch64-darwin

Sourced from https://hydra.nixos.org/log/pzhishr5vlcz8d05djgyc5j3p6a2rrzv-python3.13-xapian-1.4.31.drv.

• xapian_wrap.cc:6059:16: warning: null passed to a callee that requires a non-null argument [-Wnonnull]
   6059 |         return NULL;
        |                ^~~~
  

• xapian_wrap.cc:6066:18: warning: null passed to a callee that requires a non-null argument [-Wnonnull]
   6066 |           return NULL;
        |                  ^~~~