Refactor CI

[jakoschiko]

Okay... I neither understand GitHub Actions nor YAML... but I tried very hard!

The most important change is this:

    strategy:
      matrix:
        rust:
          - version: 1.58.1
            run-all: false
          - version: 1.80.1
            run-all: true

Now we have a variable run-all that we can use as a condition for tasks like cargo test. Easy.

      - name: Check lib
        run: $HOME/.cargo/bin/cargo check --lib

      - name: Check all
        # We can't use --all-targets because it includes benches which requires nightly compiler
        run: $HOME/.cargo/bin/cargo check --workspace --lib --bins --examples --tests
        if: ${{ matrix.rust.run-all }}

This works! I kept the older Rust version (1.58.1) because it tests the MSRV. But I increased the newer Rust version (1.61.0 -> 1.80.1) because it allows us to use shiny new stuff in tests and benchmarks.

Btw your cache didn't work. I think I fixed it. Previously you used the non-existing variable matrix.build. This resulted in this nice message:

Cache not found for input keys: -cargo-d04301ae37762a1e12b9e0e0deded45da81bd6e399ca943d66a6bb119bdd84c6, -cargo-

I was able to fix it by changing matrix.build to matrix.rust.version:

Cache restored successfully
Cache restored from key: 1.58.1-cargo-17a98d4477ebac4c9d1946e91ee5e564748d097ff95913d6e38944be8f2bdfb1

And one more think. I remove the line rustup component add rustfmt because it seems to be installed by default. This output was emitted before my change:

info: component 'rustfmt' for target 'x86_64-unknown-linux-gnu' is up to date

[jakoschiko]

I want to highlight the execution time :p

[JesperAxelsson]

Ya, I think the CI script were quite out of date. Thank you for fixing them, the new timings look great!