Fixed [Playground] DeployExamples, modified "get difference" step, execution tr…

[MakarkinSAkvelon]

The following flow will be applied:
Once a [Playground] merged to master branch, this pipeline will be triggered. It executes both jobs: collect examples and deploy examples. The change between examples is controlled by "get Difference" step: it's compare previous commit with the current one (git diff --name-only ${{ github.event.before }} ${{ github.event.after }}) (assuming that all PRs are squashed to 1 commit on merge to master). Pipeline trigger was also change: Now it will execute once pull request will me merged

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[VladMatyunin]

R: @pabloem

[VladMatyunin]

There is an assumption: "... all PRs are squashed to 1 commit on merge to master".
I've checked some PRs in the repository, and seems like there are all squashed before merge. Please LMK if you have concerns on that.

[pabloem]

lgtm

[pabloem]

... wait - we don't always squash commits before merging. Do you htink we could use the branch in the PR and compare against master before the merge?

[pabloem]

seems like this may be possible (https://docs.github.com/en/developers/webhooks-and-events/webhooks/webhook-events-and-payloads)

[VladMatyunin]

... wait - we don't always squash commits before merging. Do you htink we could use the branch in the PR and compare against master before the merge?

The problem with this is that the PR may come from a fork and it won't be assumed as protected branch. Therefore, the secrets won't work there and the pipeline won't be able to authenticate to GCP.
I'll explore the web hook approach, thank you, Pablo!