Unable to select using `--inference-accelerators`

[dims]

the following does NOT work:

❯  ec2-instance-selector --vcpus 8 --gpus 0 --memory 16GiB -a x86_64 --inference-accelerators 1
NOTE: The criteria was too narrow and returned no valid instance types. Consider broadening your criteria so that more instance types are returned.

However the following work fine:

❯ ec2-instance-selector --vcpus 8 --gpus 0 --memory 16GiB -a x86_64 --inference-accelerator-manufacturer AWS
inf1.2xlarge

❯ ec2-instance-selector --vcpus 8 --gpus 0 --memory 16GiB -a x86_64 --inference-accelerator-model Inferentia
inf1.2xlarge

[dims]

Fixed in #414