Added ASAv 9.16.2 (CML version) to cisco-asav.gns3a

Before submitting a pull request, please check the following.

When updating an existing appliance:

[x] The new version is on top.
[-] The filenames in the "images" section are unique, to avoid appliances / version overwriting each other.
Cisco Modeling Labs (Personal) v 2.4.0 has same filename as production ASAv 9.16.2
[-] If you forked the repo, running check.py doesn't drop any errors for the updated file.
Duplicate filename for cisco-asav-9-16-2.qcow2, referenced above and in #678

When creating a new appliance: N/A
It's tested locally, i.e.
- [ ] You dragged an instance into a project on your box, got it installed (if necessary), and did some basic network checks (ping, UI reachable, etc.).
- [ ] GNS3 VM can run it without any tweaks.
- [ ] The device is in the right category: router, switch, guest (hosts), firewall
- [ ] You filled in as much info as possible (checks the schemas and other appliance files for some guidance).
[ ] When adding a container: it builds on Docker Hub and can be pulled.
[ ] The filenames in the "images" section are unique (to avoid appliances and/or versions overwriting each other).
[ ] If you forked the repo, running check.py doesn't drop any errors for the new file.
[ ] Optional: a symbol has been created for the new appliance.

GNS3 / gns3-registry