Pull Request Overview

This PR replaces the ecdsa library with the cryptography library for handling ECDSA signature verification in the SendGrid Python SDK. This change affects the event webhook functionality that validates incoming webhook signatures from SendGrid.

Key changes:

• Replaces ecdsa dependency with cryptography in package requirements
• Updates imports and signature verification logic in the EventWebhook class
• Updates documentation references across README and CONTRIBUTING files

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 3 comments.

This PR successfully addresses the security vulnerabilities in the ecdsa dependency by migrating to the industry-standard cryptography library. The implementation is clean and maintains backward compatibility.

Minor Suggestion:

Version Constraint: Consider if cryptography>=45.0.6 is too restrictive - you might want to allow a broader range like >=45.0.6,<46 to avoid forcing users to upgrade to very recent versions.