🌱 Migrate Maintained check to probes

[AdamKorcz]

What kind of change does this PR introduce?

Feature.
(Is it a bug fix, feature, docs update, something else?)

• PR title follows the guidelines defined in our pull request documentation

What is the current behavior?

What is the new behavior (if this is a feature change)?**

This rewrites the Maintained check to four different probes:

1. archived: Checks whether a project is archived.
2. activityOnIssuesByCollaboratorsMembersOrOwnersInLast90Days: Checks whether project collaborators, members or owners have participated in issues in the last 90 days.
3. commitsInLast90Days: Checks whether the project has had any commits by any user type in the last 90 days.
4. wasCreatedInLast90Days: Checks whether the project was created in the last 90 days.

Put together, these four probes do the same checks as the current Maintained check. There should not be change in scoring, but the unit tests for the Maintained check and evaluation was not extensive, so this requires a review.

A few good-to-knows about the probes:
The outcome of archived may confuse some users: If the project is archived, the outcome is negative, because it is a negative factor. Some users may expect that a negative outcome means "no: The project is not archived".

I believe commitsInLast90Days and activityOnIssuesByCollaboratorsMembersOrOwnersInLast90Days are the first probes to return a numeric value instead of true/false. However, there are no changes to the internals of Scorecard, since each probe is already designed to return a slice instead of a single finding.

The probes are named according to the time they check.

The current Maintained check is not completely aligned with the documentation. For example, the documentation specifies that Maintained checks for commits every week whereas this is not the case in the implementation. The implementation checks that the contributions on average equal one contribution per week. This PR does NOT fix that, and I argue this PR should not fix that, since there are some considerations to make about the scoring.

• Tests for the changes have been added (for bug fixes/features)

Does this PR introduce a user-facing change?

No

For user-facing changes, please add a concise, human-readable release note to
the release-note

[codecov]

Codecov Report

Merging #3507 (25b079d) into main (be0b915) will decrease coverage by 5.54%.
The diff coverage is 79.89%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3507      +/-   ##
==========================================
- Coverage   76.13%   70.59%   -5.54%     
==========================================
  Files         205      209       +4     
  Lines       14068    14217     +149     
==========================================
- Hits        10711    10037     -674     
- Misses       2725     3592     +867     
+ Partials      632      588      -44     

[github-actions]

Stale pull request message

[spencerschrock]

main blocker is the finding repetition vs value fields. happy to discuss in slack as well