Fix size deltas report infrastructure configuration

[per1234]

Revert Size Deltas Report Infrastructure Back to Public Repository-Appropriate Configuration

The repository infrastructure uses the arduino/report-size-deltas GitHub Actions action to generate a report of the changes in memory usage of the example sketches that would result from merging a pull request.

There are two use patterns for the arduino/report-size-deltas action:

• Run from a workflow triggered by a schedule event
• Run from the same workflow as the "arduino/compile-sketches" action when triggered by a pull_request event

The latter use pattern is only suitable for private repositories. The reason is that, when a pull request is submitted from a fork, the permissions of the access token used by the arduino/report-size-deltas action are downgraded to read-only in workflows triggered by a pull_request event, which means it is unable to make the report comment.

The reverted commit migrated the size deltas report infrastructure from the first use pattern to the second, which caused the "Compile Examples" workflow runs to fail on pull requests submitted from forks:

https://github.com/arduino-libraries/ArduinoIoTCloud/actions/runs/7985568163/job/21816272872?pr=427#step:4:18

Error: HTTPError: HTTP Error 403: Forbidden

For this reason, the infrastructure must be reverted back to using the first use pattern.

Fix Regression in Size Deltas Report Infrastructure Configuration

The sketches-reports-source input of the arduino/report-size-deltas action defines the regular expression that matches the names of the sketches report workflow artifacts produced by the "Compile Examples" workflow.

The key string in the names of these artifacts was set to "sketches-report" when the "Compile Examples" workflow was adjusted for compatibility (#423) with the breaking changes introduced by updating to version 4.x of the workflow's actions/upload-artifact GitHub Actions action dependency (#419):

ArduinoIoTCloud/.github/workflows/compile-examples.yml

Line 303 in 836771a

name: sketches-report-${{ matrix.board.artifact-name-suffix }}

The pattern set in the size deltas report workflow was "sketches-reports":

ArduinoIoTCloud/.github/workflows/report-size-deltas.yml

Line 14 in c2a9992

sketches-reports-source: sketches-reports

The s at the end of that pattern caused it to no longer match against the key string in the artifact names after that adjustment of the "Compile Examples" workflow, resulting in size deltas reports no longer being generated by the workflow.

Although a minimal fix would be to simply remove the s from the end of the pattern, the decision was made to use a more strict regular expression. This will make it easier for maintainers and contributors to understand that this value is a regular expression and the exact nature of how that regular expression functions (which is less clear when relying on the arduino/report-size-deltas action's partial pattern matching behavior).

[per1234]

Note for reviewers:

The re-added report-size-deltas.yml workflow will only start being triggered after this pull request is merged. So it is expected that there won't be a report comment on this pull request.

[aentinger]

Per, thank you very much for the detailed explanation 🙇 . Superb work!