feat: add amz-content-sha256 extension to docs (#3036)

www/content/extensions/_index.md

@@ -50,3 +50,4 @@ htmx extensions are split into two categories:
 | [restored](https://github.com/bigskysoftware/htmx-extensions/blob/main/src/restored/README.md)                           | Triggers an event whenever a back button even is detected while using `hx-boost`                                                                                                                                                                                                              |
 | [safe-nonce](https://github.com/MichaelWest22/htmx-extensions/blob/main/src/safe-nonce/README.md)                        | The `safe-nonce` extension can be used to improve the security of the application/web-site and help avoid XSS issues by allowing you to return known trusted inline scripts safely                                                                                                            |
 | [signalr](https://github.com/Renerick/htmx-signalr/blob/master/README.md)                                                | Provides bidirectional real-time communication via [SignalR](https://github.com/dotnet/AspNetCore/tree/main/src/SignalR).                                                                                                                                                                     |
+| [amz-content-sha256](https://github.com/felipegenef/amz-content-sha256/blob/main/README.md)                              | HTMX extension for interacting with AWS services that require the content hash as part of the request for data integrity verification.                                                                                                                                                        |