Remove broken and unused stats workflows

[per1234]

Motivation

The "arduino-stats" GitHub Actions workflow was designed to periodically gather download statistics from Arduino CDN and push results to Datadog (a46f36a).

The recorded stats from the identical system in the Arduino CLI repository showed a periodic decrease in total download count. Since this is patently impossible, it is clear that something is wrong with the system and that the recorded data is not trustworthy. An investigation into the problem was never done.

On 2022-03-14, the runs of the "arduino-stats" GitHub Actions workflow began to fail:

Traceback (most recent call last):
  File "/home/runner/work/arduino-ide/arduino-ide/.github/tools/fetch_athena_stats.py", line 127, in <module>
    exec_id = execute(athena_client, query, DEST_S3_OUTPUT)
  File "/home/runner/work/arduino-ide/arduino-ide/.github/tools/fetch_athena_stats.py", line 27, in execute
    wait_for_query_execution_completion(client, execution_id)
  File "/home/runner/work/arduino-ide/arduino-ide/.github/tools/fetch_athena_stats.py", line 40, in wait_for_query_execution_completion
    raise BaseException(
BaseException: query failed or canceled: INVALID_FUNCTION_ARGUMENT: URLDecoder: Illegal hex characters in escape (%) pattern - For input string: "b "

Because there had not been any relevant change in the repository between the last successful run and the first failing run, it seems likely that some external change caused the breakage.

Since the "arduino-stats" workflow was not ever working successfully and there was never an investigation about that, nor any investigation or impact resulting from the last 6 months of failed workflow runs, it is clear the stats are not of any value.

The "github-stats" GitHub Actions workflow periodically gathers GitHub release asset download statistics for Arduino CLI and pushes the results to Datadog.

There are no known problems with the "github-stats" workflow. However, GitHub stats are not very valuable on their own as they only provide an unknown fraction of the total downloads of Arduino IDE. So there is no point in keeping this workflow after the "arduino-stats" workflow is removed. As with the data from the "arduino-stats" workflow, this information has never ended up being used.

Both workflows use deprecated Node.js 12 runtime-based actions:

https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/

and set-output workflow commands:

https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

These currently result in warnings printed to the workflow run summary page, but will eventually cause the complete breakage of the workflow.

Change description

Remove the broken infrastructure from the repository rather than investing time into fixing and maintaining something that isn't being used anyway.

Other information

Fixes #971

The workflows were removed from the Arduino CLI repository last April without any detrimental affect:

• [skip changelog] Remove broken download stats workflow arduino-cli#1701
• [skip changelog] Remove unused GitHub release download stats workflow arduino-cli#1702

Reviewer checklist

• PR addresses a single concern.
• The PR has no duplicates (please search among the Pull Requests before creating one)
• PR title and description are properly filled.
• Docs have been added / updated (for bug fixes / features)

[kittaakos]

It makes sense to remove it. Thank you!