feat: use cache when deploy on github pages

[tiennm99]

I think use GitHub Action Cache to cache resources directory is a good practice when deploy on GitHub Pages. It helps build faster, especially when we have many resource like images or scss that need to be processed.

[jmooring]

This is a great idea, but I'd to change the implementation. With what you propose, will we not cache remote resource calls or modules. This is the default configuration for our file cache:

https://gohugo.io/configuration/caches/

We should instruct users to override the image cache location by placing this in their site configuration:

  [caches.images]
    dir = ':cacheDir/_gen'
    maxAge = -1

Then we need to pass the --cacheDir something flag to the build command. Please test the setup before resubmitting the PR. Thanks!

EDIT: I'm pretty sure that GitHub Pages doesn't cache the node_modules directory. So, while the body is open...

[jmooring]

We should have done this a long time ago.

[tiennm99]

Thank you for your comment. I will improve it.