Custom storage for SCORM xblock

[naumanshafi]

PR Description

Summary:
Implement a custom storage solution to store and retrieve data from a private S3 bucket. Modify the handling of SCORM content requests loaded via JavaScript from a primary file, ensuring they are routed through a custom XBlock view instead of directly accessing the S3 storage. All SCORM XBlock resource requests should be intercepted by the custom view to add signatures before forwarding them to the S3 storage, allowing secure access to private content. Additionally, the ability to read SCORM content from a private bucket should be configurable via Django settings.

Changes Made:

• Created a custom storage implementation to facilitate data storage in a private S3 bucket.
• Implemented a custom XBlock view to handle SCORM content requests.
• Modified the routing of SCORM XBlock resource requests to pass through the custom view for signature addition.
• Added configuration options in Django settings to control the reading of SCORM content from a private bucket.

Motivation:
This PR addresses EDE-2041, the Jira issue discussing the need for secure storage and retrieval of SCORM content. By leveraging a private S3 bucket and introducing a custom XBlock view, we ensure that SCORM content requests are processed securely with the addition of signatures. The configurable settings enable flexibility in managing access to SCORM content stored in private buckets.

Additional Notes:

• The custom storage solution follows best practices for secure data handling and authentication.
• The custom XBlock view integrates seamlessly into the existing SCORM content loading process.
• The provided Django settings allow for easy configuration of the SCORM content retrieval from private buckets.

Related Issues

• EDE-2041: Discusses the need for secure storage and handling of SCORM content.

Configuration Changes (lms/envs/private.py and cms/envs/private.py)

# XBlock settings for ScormXBlock
XBLOCK_SETTINGS["ScormXBlock"] = {
    "STORAGE_FUNC": "openedxscorm.storage.s3",
    "SCORM_S3_BUCKET_NAME": "<your-bucket-name>",
    "SCORM_S3_QUERY_AUTH": True,
    "SCORM_S3_EXPIRES_IN": 86400
}

[ziafazal]

@naumanshafi I have added few questions and a suggestion. Could please look into those?