support: postcss not work correctly

[elct9620]

Checklist

• I am using the latest version of this action.
• I have read the latest README and followed the instructions.
• I have read the latest GitHub Actions official documentation and learned the basic spec and concepts.

Describe your question

It does not work correctly when using PostCSS with PrugeCSS to clean CSS.

• Use npx postcss -r public/css/*.css work correctly to clean CSS with hugo_stats.json
• Use resource.PostCSS work incorrect which clean all CSS and didn't reference hugo_stats.json and the defaultExecutor didn't called.

Use the same config to run hugo --minify in local machine (macOS) is work correctly.

Relevant links

Public repository: https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/tree/main
YAML config: https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/blob/main/config.toml
YAML workflow: https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/blob/main/.github/workflows/publish.yml

Relevant log output

Start building sites … 
hugo v0.101.0-466fa43c16709b4483689930a4f9ac8add[5](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:6)c9f[6](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:7)6+extended linux/amd64 BuildDate=2022-06-16T07:09:16Z VendorInfo=gohugoio
INFO 2022/07/04 17:18:55 syncing static files to /
DEBUG 2022/0[7](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:8)/04 17:1[8](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:9):55 Render page 光之角落 SunnyCorner B&B to "/index.html"
INFO 2022/07/04 17:18:55 postcss: use config file /home/runner/work/sunnycorner-bb.github.io/sunnycorner-bb.github.io/postcss.config.js
INFO 2022/07/04 17:18:56 postcss: npm
INFO 2022/07/04 17:18:56 postcss:  notice
INFO 2022/07/04 17:18:56 postcss:  
INFO 2022/07/04 17:18:56 postcss: npm notice New minor version of npm available! 8.12.1 -> 8.13.2
INFO 2022/07/04 17:18:56 postcss: npm
INFO 2022/07/04 17:18:56 postcss:  
INFO 2022/07/04 17:18:56 postcss: notice
INFO 2022/07/04 17:18:56 postcss:  Changelog: <https://github.com/npm/cli/releases/tag/v8.13.2>
INFO 2022/07/04 17:18:56 postcss: npm notice Run `npm install -g npm@8.13.2` to update!
npm notice 
DEBUG 2022/07/04 17:1[9](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:10):02 Render XML for "sitemap" to "/sitemap.xml"
DEBUG 2022/07/04 [17](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:18):[19](https://github.com/sunnycorner-bb/sunnycorner-bb.github.io/runs/7184724032?check_suite_focus=true#step:8:20):02 Render page 光之角落 SunnyCorner B&B to "/index.xml"

Additional context.

The postcss.config.js is correctly loaded. But the purgecss plugin seems not to use the correct config.

If set defaultExtractor to return the [] will get same result in local machine.