Build environment for lacti-blog
GitHub Actions is awesome but it is slower than Travis-CI now and I found it is slow to download all packages about Gatsby.js.
I think it can be fast when it downloads its environment via Docker instead of npm repository so I build and cache its node_modules in this docker image.
... But, it is only about 10~20 seconds reduced rather than downloading node packages directly. I hope GitHub actions would be cached docker layers more efficiently as soon.