AdvertiseHostname not passing validation

[bonzi]

Describe the bug

Setting AdvertiseHostname results in pathvector failing to generate a valid config for bird.

FATA[0005] BIRD: BIRD validation error:
        import limit AS1234_COMPANY_IMPORT_v4 action disable;
        advertise hostname on;
        ^ syntax error, unexpected ADVERTISE

Environment

1. Output from pathvector version

Pathvector 6.3.2
Built c35220bf121f366ff05a51d93c6236e8c324d682 on 2023-06-11T07:03:14Z
No plugins
BIRD: ready.

2. OS version Debian GNU/Linux 12 (bookworm) x86_64
3. Minimum reproducible example of your Pathvector config file formatted with triple backticks with yaml language identifier

...
hostname: router.as1234.net
...
  AS112:
    asn: 112
    description: AS112
    template: downstream
    neighbors:
      - 100.100.100.112
    announce-hostname: true
...

To Reproduce Steps to reproduce the behavior:

1. Implement hostname, and advertise-hostname
2. Run pathvector g
3. See error

Expected behavior Pathvector should generate a valid config