Charmcraft build fails because Lunar 23.04 images are no longer available

[Jadon Naas]

The Charmcraft build failed for the Vault charm on OpenDev recently because charmcraft could not launch an instance to build the charm for lunar/23.04. Here is the relevant error logs:

2024-04-30 15:26:12.859 Failed to launch instance base-instance-charmcraft-buildd-base-v80-4906736a6077a3760c4e, retrying 0.
2024-04-30 15:26:12.859 Command '['lxc', '--project', 'charmcraft', 'launch', 'ubuntu-daily:lunar', 'local:base-instance-charmcraft-buildd-base-v80-4906736a6077a3760c4e', '--config', 'raw.idmap=both 1000 0', '--config', 'security.syscalls.intercept.mknod=true', '--config', 'user.craft_providers.status=STARTING', '--config', 'user.craft_providers.timer=2024-04-30T19:26:11.623913+00:00', '--config', 'user.craft_providers.pid=54747']' returned non-zero exit status 1.
2024-04-30 15:26:12.859 Failed to launch instance 'base-instance-charmcraft-buildd-base-v80-4906736a6077a3760c4e'.
2024-04-30 15:26:12.859 Detailed information: * Command that failed: "lxc --project charmcraft launch ubuntu-daily:lunar local:base-instance-charmcraft-buildd-base-v80-4906736a6077a3760c4e --config 'raw.idmap=both 1000 0' --config security.syscalls.intercept.mknod=true --config user.craft_providers.status=STARTING --config user.craft_providers.timer=2024-04-30T19:26:11.623913+00:00 --config user.craft_providers.pid=54747"
* Command exit code: 1
* Command output: b'Creating base-instance-charmcraft-buildd-base-v80-4906736a6077a3760c4e\n'
* Command standard error output: b'Error: Failed instance creation: Failed getting remote image info: Failed getting image: The requested image couldn\'t be found for fingerprint "lunar"\n'

We do not need to target lunar/23.04 anymore.

The review this happened in is at https://review.opendev.org/c/openstack/charm-vault/+/917766.

[Jadon Naas (jadonn)]

I'm going to get a change up to remove lunar/23.04 from charmcraft.yaml.