fix: CI - The assign/unassign GitHub Action is not working

[hoangnv-bkhn]

Description

• Problem:
  The takanome-dev/assign-issue-action (currently used) only works properly when assigning issues, not when unassigning.

• The way it was resolved:

  • With assign assignees:
    Use custom script to check comments containing /assign-me to specify assignees, add necessary labels and comments
  • With unassign assignees
    Use actions/stale@v9 to check for stale issues when specified conditions are met
    Use custom script to unassign and delete specific labels

• How to test the change:
  Change workflow schedule (cron), number of days before being marked as stale (env.DAYS_UNTIL_STALE) in unassign-issue.yml, and check

• Note:
  In my previous PR, this line was not covered so I added a test case for it.

Closes issue(s)

Resolve #2313

Checklist

• I have tested this code
• I have added unit test to cover this code
• I have updated the documentation (README.md and /website/docs)
• I have followed the contributing guide

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.84%. Comparing base (7333bfe) to head (830d56f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2529      +/-   ##
==========================================
+ Coverage   85.79%   85.84%   +0.05%     
==========================================
  Files         100      100              
  Lines        3554     3554              
==========================================
+ Hits         3049     3051       +2     
+ Misses        379      378       -1     
+ Partials      126      125       -1     

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[thomaspoignant]

Thanks for this PR.
Let's hope that it will work better than the GH action.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud