[skip-changelog] Use a matrix to create parallel builds for each OS

[MatteoPologruto]

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• Tests for the changes have been added (for bug fixes / features)
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What kind of change does this PR introduce?

Infrastructure Enhancement

What is the current behavior?

Release-go-task, publish-go-nightly-task and publish-go-tester-task are currently using task dist:all to build and create the release artifacts. This is done by calling the tasks related to each OS consecutively. As a result, the finishing time of task dist:all is the sum of the finishing times of each individual dist. Furthermore, the checksums related to the files built are calculated more than once, unnecessarily.

What is the new behavior?

• Using a matrix to run each build task greatly improves performance, since they can all start concurrently. The finishing time of the job will be equal to the one of the longer task to build, instead of being the sum of each individual task's finishing time.
• Checksums are only being calculated once, during the final steps of the workflows.
• A check has been introduced to avoid creating the same changelog for each parallel building job.
• publish-tester-build now uploads a different artifact for each build during the first job, instead of creating a combined one that needs to be split later.

Does this PR introduce a breaking change, and is titled accordingly?

No

Other information:

Release run: https://github.com/MatteoPologruto/arduino-cli/actions/runs/3128175485
Test release: https://github.com/MatteoPologruto/arduino-cli/releases/tag/0.0.3
Nightly build run: https://github.com/MatteoPologruto/arduino-cli/actions/runs/3128099818
Tester build run: https://github.com/MatteoPologruto/arduino-cli/actions/runs/3137219983

Publish-go-tester-task was correctly skipped after run-determination when I pushed the tag 0.0.2 onto my fork (here). Out of curiosity, I triggered the workflow run manually on the same commit and the checksums' calculation was not correct (here). Checksums calculated previously and afterwards seem to be correct, even though the workflow has not been modified. I think it might be worth mentioning.

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[umbynos]

Wow! The improvement in time is huge! 🚅
Unfortunately this is not sufficient: we need to find another approach for the checksum generation, because the generated one is not complete.
The task dist:all was appending the checksums in the same file and then uploading it (since the task were executed sequentially it was possible). Unfortunately this is no longer working.
I suggest removing the checksum calculation from the tasks, from the notarization step. And perform it only during the release creation job

[umbynos]

Also it does not make sense to perform the changelog generation in all the jobs.. could be an idea to do it only for one of the runs

[umbynos]

I've just noticed an unrelated problem with the release CI:

arduino-cli/DistTasks.yml

Line 214 in a3f6574

PLATFORM_DIR: "{{.PROJECT_NAME}}_linux_arm_6"

This should be:
PLATFORM_DIR: "{{.PROJECT_NAME}}_linux_arm_64"
It's worth to fix it in this PR IMHO.
More context here

[umbynos]

Left some suggestions 👾

[umbynos]

Great Job Matteo 🥇