feat(CLI): Automatically expand loaded env variables

[d-asensio]

Closes: #9689

[pgrzesik]

Hello @d-asensio - could you please include motivation behind this PR proposal? I believe there is not corresponding issue created for that, correct?

[d-asensio]

Hey @pgrzesik sure! I found some time to write an issue with the motivations of this. I referenced it in my first comment.

Thank you!

[pgrzesik]

Thanks a lot @d-asensio - it looks great overall and thanks so much for writing up a motivation in a linked issue. I think it's a good idea to allow such expansions, but it would also be good to document it e.g. here: https://github.com/serverless/serverless/blob/master/docs/environment-variables.md

Btw - it looks like there's a conflicting file - could you please look into that and rebase your branch?

[d-asensio]

Hey, @pgrzesik I rebased it onto master and added a comment with a little example in the docs.

Thank you!

[d-asensio]

Hi @pgrzesik, is there something missing here?

[pgrzesik]

Thanks a lot 🙇 Sorry for the delay in review - I missed the notification and then I was off for a few days. I have one minor suggestion related to docs - also, let's wait for opinion from @medikoo if we should introduce such extensions.

[codecov]

Codecov Report

Merging #9615 (1a44ea0) into master (7078449) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 1a44ea0 differs from pull request most recent head fd4b4ff. Consider uploading reports for the commit fd4b4ff to get more accurate results

@@           Coverage Diff           @@
##           master    #9615   +/-   ##
=======================================
  Coverage   86.10%   86.10%           
=======================================
  Files         328      328           
  Lines       12590    12594    +4     
=======================================
+ Hits        10840    10844    +4     
  Misses       1750     1750           

Impacted Files	Coverage Δ
lib/cli/load-dotenv.js	95.23% <100.00%> (+1.12%)	⬆️

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[medikoo]

@d-asensio @pgrzesik it feels as great addition to me. It mimicks how things will work in a shell, which is a nice improvement.

@pgrzesik After adjustment to docs is made, feel free to merge

[pgrzesik]

Thanks @medikoo 🙇 @d-asensio so the only thing to address is one comment about attributing what library is used for expansions and we're good to go 👍

[d-asensio]

Done! Thank you both @pgrzesik and @medikoo! 🥳 🎉

[pgrzesik]

Thank you @d-asensio, well done 👏