strongswan: 5.6.2 -> 5.6.3 (#41237)

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

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

These checks were done:

- built on NixOS
- /nix/store/9qicaqwg2cvmahh3hqwig5bcqpd41k9a-strongswan-5.6.3/bin/pki passed the binary check.
- /nix/store/9qicaqwg2cvmahh3hqwig5bcqpd41k9a-strongswan-5.6.3/bin/charon-cmd passed the binary check.
- Warning: no invocation of /nix/store/9qicaqwg2cvmahh3hqwig5bcqpd41k9a-strongswan-5.6.3/bin/charon-systemd had a zero exit code or showed the expected version
- /nix/store/9qicaqwg2cvmahh3hqwig5bcqpd41k9a-strongswan-5.6.3/bin/ipsec passed the binary check.
- /nix/store/9qicaqwg2cvmahh3hqwig5bcqpd41k9a-strongswan-5.6.3/bin/swanctl passed the binary check.
- 4 of 5 passed binary check by having a zero exit code.
- 1 of 5 passed binary check by having the new version present in output.
- found 5.6.3 with grep in /nix/store/9qicaqwg2cvmahh3hqwig5bcqpd41k9a-strongswan-5.6.3
- directory tree listing: https://gist.github.com/258736889db4e822d054b65e7035147b
- du listing: https://gist.github.com/478dbb4f44b4ed18b112076b17451a4e