feat: enhance organization webhook creation script

[joshjohanning]

• Added usage instructions and argument validation, including default and common event suggestions, to guide users and prevent incorrect usage.
• Allows dynamic specification of webhook events, defaulting to push if none are provided, making the script more flexible.
• Added logic to detect and warn about using OAuth tokens (which have management limitations) and recommend Personal Access Tokens for webhook management.
• Improved output messages to clearly indicate the webhook creation process and token type being used.
• Refactored the webhook creation API call to use the provided arguments and events, ensuring the correct configuration is sent to GitHub.