travis pipeline is slow

[meltinglava]

The pipline takes significant ammount of time. Think there is a better way of doing this.

• 1. run cargo bench --no-run insdead of cargo bench as they take a while and I suspect results are not looked at. Feel like benchmarking results are better run locally. Checking that they build would always be nice. merged in Do not run benchmarks in the pipline. #426

• 2. Building on all platforms, while just running test, check, (fmt, clippy)... on one toolchain (stable or nightly)

• 3. Add caching for builds and compiler. ref: https://docs.travis-ci.com/user/languages/rust/#dependency-management. Ref add caching to travis #429

[bluss]

I think it's time to migrate from travis-ci.org - they are closing down. Github Actions should be an ok replacement?

[jswrenn]

Agree completely.

[Philippe-Cholet]

I think we can close this now that clippy is in our (github actions) CI.