gpg: Allow smaller session keys with Kyber
* g10/pubkey-enc.c (get_it): Do not error out when decrypting a session key of less than 32 octets encrypted to a Kyber key.
- GnuPG-bug-id: T7472
- Signed-off-by: Damien Goutte-Gattat <dgouttegattat@incenp.org>