Run tests on Arm Virtual Hardware

[jonathanpallant]

Arm now have a walkthrough for setting up an Arm Virtual Hardware as an EC2 instance, and connecting to that from GitHub Actions.

https://catalog.us-east-1.prod.workshops.aws/workshops/30043722-0362-4859-bc6f-c28836a2d7ac/en-US

Sounds like perhaps a better place to test the cortex-m crate (and friends) than QEMU, or on random hardware in a cupboard. Although it's not free of charge, there is an OSS discount.