⚠️ Move the cron job to internal package

[azeemshaikh38]

What kind of change does this PR introduce?

Reduces exposed APIs by moving cron to internal package.

(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)?**

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

Which issue(s) this PR fixes

NONE

Special notes for your reviewer

Does this PR introduce a user-facing change?

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application as a result of this pull request.)

Removes `cron` package from exposed APIs.

[naveensrinivasan]

This is should be a breaking change. Though technically no one should be using it. Let's still call it a breaking change.

[codecov]

Codecov Report

Merging #1960 (fc9a703) into main (6a21afb) will increase coverage by 3.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1960      +/-   ##
==========================================
+ Coverage   50.79%   53.84%   +3.05%     
==========================================
  Files          83       83              
  Lines        6719     6719              
==========================================
+ Hits         3413     3618     +205     
+ Misses       3078     2867     -211     
- Partials      228      234       +6     

[github-actions]

Integration tests success for
[a5ff62b]
(https://github.com/ossf/scorecard/actions/runs/2387257865)

[github-actions]

Integration tests success for
[fc9a703]
(https://github.com/ossf/scorecard/actions/runs/2387360926)