Migrate from circle ci to github actions

[dany-pellerin]

This PR migrates from CircleCI to GH actions.

For context, the Makefile is used for development and was used in CircleCi. The vanilla-demo job uses the makefile to build the vanilla files, however for the lib, web and other demos, the makefile can't make use of the cache and installs all dependencies every time it runs which could become costly in the long run and also can't run the tasks concurrently.

The github actions that were created also output the artifacts which will make it a lot easier to debug if an issue arises.

The deploy on CircleCi was using gsutil which is a legacy tool (see https://cloud.google.com/storage/docs/gsutil). The github steps in the workflows use official actions. For the deploy if there's an issue with publishing on npm, the other steps won't run (deploying the SDK to GCS and the demo for google storage artifacts).

The deploy steps are fairly complex and were very hard to test:

• we need to deploy the sdk to npm
• we need to deploy multiple versions of the SDK to GCS (depends on the version, a matrix was used to handle that)

Example

• we deploy the demo-images docker image to GC artifacts

All steps have been tested except the following:

• publishing on npm was tested using the -dry-run flag
• uploading the SDK to gcs (it will be tested on the next release, we can do it manually and fix the workflow)
• uploading the demos to google artifacts (it will be tested on the next release, we can do it manually and fix the workflow)

These changes mimic the same behavior that the CircleCi was doing, however we typically use terraform for deploying and the deploy steps should probably be moved to terraform. This should be addressed in the future.

Also, the bash script that checks for the versions to publish would need to be converted to a reusable github action. It installs dependencies (it needs semver) needlessly, it's hard to manually run. It could easily be created using a javascript action, it would be a lot easier to test, would be more robust and performant. This might be done in the future. Since the deploy rarely runs, it's not a problem for now.

The script I created can be used for any package available in npm to manually test the different scenarios. It doesn't upload anything, it only returns an array which contains the versions that need to be updated.
useage example: ./scripts/versions-to-update.sh core-js v1.5.10

[souzamari]

Great job! I left some small comments. As for the service account for CD we will most likely have to update it, but I think there is some work to be done in terraform since the default name is "gh-ci-..."

small items to address before merge

[souzamari]

LGTM. I would still get Antoine feedback/review for the release workflow and the version update since he is the expert on it ;)