Unlock tasks after validation using in parallel using python threads

[kaditya97]

• fix Tasks validation using python threads #6244
• fix [BUG] Unable to submit tasks after validation #6154
• Uses Python multiprocessing pool to run validation tasks in parallel using available CPU cores
• Local session for thread implementation for validation-related tasks
• Test case-related validation modified to get task by taskId instead of index as threading may sometimes return task which do not follow order

[sentry-io]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: backend/services/validator_service.py

Function	Unhandled Issue
unlock_tasks_after_validation	AttributeError: 'NoneType' object has no attribute 'last_validation_date' tasksa... Event Count: 1

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[sonarcloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[robsavoye]

Using SQLAlchemy sessions should fix the problem with thread contention when accessing the database. I can't run the backend yet, do the tests now pass ?

[kaditya97]

Using SQLAlchemy sessions should fix the problem with thread contention when accessing the database. I can't run the backend yet, do the tests now pass ?

I used new SQLAlchemy session in each thread and passed the session as local session and it worked. Also all test are passing now.