scripts: Fix download.osv.io S3 bucket name

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
scripts: Fix capstan release upload

We can no longer use "--delete-removed" because the S3 bucket hosts
Capstan executables and access logs.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>