* Bump actions/cache to v4 to suppress node warnings
* Respect `PUB_CACHE` from the environment
* Cache pub-cache separately from flutter
In order to reduce the extra work that happens when you update your
pubspec.lock, don't use `hashFiles('**/pubspec.lock')` in the hash of
the flutter installation, and separately cache the `.pubspec-cache`.
Also return the `.pub-cache` to `$HOME`, since it's not part of the tool
installation.
* Fix README example of pub-cache-path and document `PUB_CACHE`
* feat: support to set architecture of SDK executable
* docs: update
* fix: try fix tests
* ci: set `fail-fast` to false
* fix: get latest version sdk
* fix: test any version
* fix: legacy version format
* fix: tests
* revert changes for `.github/workflows/workflow.yml`
* Update workflow.yml
* rename `ARCHITECTURE` to `ARCH`
* follow the existing spacing
* style: simplified code
* Update setup.sh
* style