Feature: hpc8a instances CPU count customization

> Hpc8a instances are available in a single 96xlarge size with a 1:4 core-to-memory ratio, enabling customers to right-size compute capacity by customizing the number of cores at instance launch.

It appears the hpc8a instances allow you to specify the amount of CPUs to launch with.

Looking at https://docs.aws.amazon.com/parallelcluster/latest/ug/Scheduling-v3.html it appears that there is no option tp specify this at the time.

A workaround could be defining the custom amount of CPUs in a launch template and then reference that launch template. But I have yet to test this.