With the Rust 2021 feature resolver, adding a feature like `--features=feat_os_unix` results in an error, because the individual crates do not have that feature.
- the build and test steps won't run until/unless Dependency and MSRV checks pass
- code coverage won't run until/unless the build steps all pass
## [why]
This helps make more efficient use of CI resources and can help more easily visualize
build issues from the resultant GHA dashboard flow diagram.
## [why]
`cspell` in CI started mysteriously failing mid-2021. Tracking down the
error took some time as it was not obvious from `cspell` feedback where
the issue lay. Ultimately, it was discovered that `cspell` had deprecated
use on NodeJS versions < v12 for `cspell` v5+.
`cspell` is now pinned to v4.2.8, with a maintenance note to allow an
upgrade to the `cspell` version when a version of NodeJS >= v12 is being
used in the CI.
An issue requesting better tool feedback for similar situations was also
opened on the `cspell` repo.[*]
[*]: [🙏🏻 Add warning (or error) when used on deprecated/outdated JS platform versions](https://github.com/streetsidesoftware/cspell/issues/1984)
# [why]
The tool cache is currently failing and seems to be getting further behind current
versions. The [actions-rs/install#12] issue addresses this but seems to be
languishing without any proposed solution.
[ref]: <actions-rs/install#12>
- fixes conversion of new `cargo clippy` output style to GHA annotations
## [why]
`cargo clippy` output formatting changed, using relative instead of absolute paths.
* Make clippy workspace selection more finegrained
* fixup! Make clippy workspace selection more finegrained
* fixup! Make clippy workspace selection more finegrained
* fixup! Make clippy workspace selection more finegrained
* fixup! Make clippy workspace selection more finegrained
* fixup! Make clippy workspace selection more finegrained
