CLOUDP-298151: Fix SSRF Vulnerability in MongoDB Atlas CLI Integration

[lamcodeofpwnosec]

Proposed changes

Jira ticket: CLOUDP-298151

Closes #3599

Checklist

• I have signed the MongoDB CLA
• I have added tests that prove my fix is effective or that my feature works
• I have added any necessary documentation in document requirements section listed in CONTRIBUTING.md (if appropriate)
• I have addressed the @mongodb/docs-cloud-team comments (if appropriate)
• I have updated test/README.md (if an e2e test has been added)
• I have run make fmt and formatted my code

Further comments

• isSafeURL function: This function validates that the URL provided is not an internal or unsafe address. It checks if the URL uses a safe scheme (e.g., http, https), and it ensures the host does not belong to known private IP ranges or local addresses.

• URL Validation in CreateIntegration: Before proceeding with the integration creation, the WebhookURL (or any URL input) is validated with the isSafeURL function. If the URL is found to be unsafe, it returns an error and does not proceed with creating the integration.

CWE-918