ci: discuss approach for less duplication

[phip1611]

In the multiboot2-crate, I've successfully experimented (rust-osdev/multiboot2#125) with configurable reusable workflows which simplified some things for me. We also do have duplications in multiple CI jobs.

Do you see a benefit in enabling something similar in the uefi-rs crate? For example, in https://github.com/rust-osdev/uefi-rs/blob/main/.github/workflows/rust.yml we do have 6 times a sudo apt install qemu-* step.

[nicholasbishop]

I'm down to reduce duplication, but I'm not sure how much code duplication there is in rust.yml as opposed to semantic duplication. Like it's true that many jobs install qemu and ovmf, but the details are different depending on whether the target is x86_64, ia32, aarch64, and on whether the host is Windows or Linux.

[phip1611]

Mostly obsolete since #702

I thought, the CI caching needs more boilerplate as in here: https://github.com/rust-osdev/multiboot2/blob/main/.github/workflows/_build-rust.yml#L52