Refactor action to use LHCI

[exterkamp]

This changes the underlying library from Lighthouse to Lighthouse CI

✨ New features ✨

• Asserting with lighthouserc files in addition to existing budgets.json assertions.
• Saving to temporary-public-storage
• Uploading to a Lighthouse CI server
• Running against a static-build-dir

🚩 Things that changed 🚩

• Most config moved to lighthouserc
  • Chrome flags
  • custom LH config
• Action args

📋 Things that stayed the same 📋

• budgets.json support
• Hermetic testing

For convenience of reviewing this PR, we removed all changes within node_modules. After this PR is landed (squash works for us), a yarn install will update the node_modules to add LHCI and it's dependencies.

👩‍💻 TODOs 👨‍💻

• [x] treo: update the LHCI-upload-to-private-server.yml config with new secrets
• [x] merge with master and recover URLs interpolation support #6
• [x] treo: yarn install && git commit

[exterkamp]

Awesome feedback, thanks for taking a thorough look ❤️! I fixed most things inline and resolved comments. There are a few outstanding for your consideration still. And the rest is answered here!

let's use camelCase for consistency with other configs

sgtm

let's keep it private and cheap to run by default

This sounds good, but once anyone wants to get serious about asserting, they need minimum 3 runs to avoid a flaky VM.

we need some consensus on the config option and default path for lighthouserc.json (GoogleChrome/lighthouse-ci#48).

until that gets resolved, then I think keeping us tagged to 0.3.0-alpha and waiting is a good plan?

it's going to be published under @next (until LHCI is in alpha) to keep @v1 users untouched.

👍

instead of offering many configuration options, I would ask users to use lighthouserc.json, and use .yml only for Github Action specific stuff, like env variables or special options.

sgtm, good idea!

merge support fot env vars interpolation from master.

Done, never used the Github merge UI. Was cool.