libbitcoin-network: 3.4.0 -> 3.5.0

Semi-automatic update generated by https://github.com/ryantm/nix-update tools.

This update was made based on information from https://repology.org/metapackage/libbitcoin-network/versions.

These checks were done:

- built on NixOS
- Warning: no binary found that responded to help or version flags. (This warning appears even if the package isn't expected to have binaries.)
- found 3.5.0 with grep in /nix/store/mmrl1lvrc1p8ypclg2gf36n26vhyai04-libbitcoin-network-3.5.0
- directory tree listing: https://gist.github.com/05b992f0e86e04ef0e068c378b453f8b