Implement CloudWatch Log Retention Management

[lazyperson1020]

Fixes - #4585

This PR implements retention policy management for CloudWatch logs associated with EvalAI challenges. Currently, logs are retained indefinitely, which could lead to unnecessary costs. This implementation sets appropriate retention periods based on challenge end dates.
Changes -

• Added function to calculate retention periods based on challenge end dates.
• Added function to set CloudWatch log retention policies for challenge log groups.
• Logs will be retained for 30 days after the challenge end date.
• For active challenges, logs will be retained until the end date plus 30 days.
• Retention periods are mapped to valid AWS CloudWatch values.

Reference
https://boto3.amazonaws.com/v1/documentation/api/1.26.93/reference/services/logs/client/put_retention_policy.html

[lazyperson1020]

Sir please check these functions so that I can appropriately call them in other files.

[RishabhJain2018]

Hey @lazyperson1020 , These functions looks good. Can you call this function when after you have created the task definition for AWS Fargate worker to update the log group?

[lazyperson1020]

Can you call this function when after you have created the task definition for AWS Fargate worker to update the log group?

I have called the function in challenge_approval_callback , restart_workers_signal_callback and register_task_def_by_challenge_pk.