feat(ci): add llvm-cov to template ci

[joshrotenberg]

This adds the cut/paste llvm-cov job from the docs.

I tested this by creating a project with the template and put it here: https://github.com/joshrotenberg/rust-template-llvm-cov-test

I removed the call to upload the coverage file in the workflow because it requires the token in secrets, which means the workflow fails by default, which seems bad, but I'm open to suggestions.

Fixes #44

[marcoieni]

Thanks for this!

How is the user supposed to use the lcov.info file?

It would be nice to show the coverage percentage in the readme. This repo used coveralls for this.

[joshrotenberg]

Thanks for this!

👍

How is the user supposed to use the lcov.info file?

Good question. I just added the coveralls action with just the file argument which seems to work out of the box and has a lot of configuration options: https://github.com/marketplace/actions/coveralls-github-action

The output for the run is here: https://github.com/joshrotenberg/rust-template-llvm-cov-test/actions/runs/8530312705/job/23367853431

It would be nice to show the coverage percentage in the readme. This repo used coveralls for this.

Where is this? I don't see it.

[marcoieni]

Where is this? I don't see it.

It was here