Update README.md

Author: khiga8

README.md

@@ -1,6 +1,6 @@
 # Accessibility-alt-text-bot
 
-This action supports accessible content sharing on GitHub by leaving an automated reminder whenever an image is shared on a GitHub Issue or Pull request without meaningful alternative text (alt text).
+This action supports accessible content sharing on GitHub by leaving an automated reminder whenever an image is shared on a GitHub Issue, Pull request, or Discussion without meaningful alternative text (alt text).
 Alternative text helps convey the context of the image to those who use assistive technologies such as a screen reader and removes accessibility barriers.
 
 For guidance on setting alternative text, see [Alternative text for images on Primer](https://primer.style/design/guides/accessibility/alternative-text-for-images).
@@ -85,4 +85,4 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
 
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 
-This project follows the [all-contributors](https://github.com/all-contributors/all-contributors) specification. Contributions of any kind welcome!
+This project follows the [all-contributors](https://github.com/all-contributors/all-contributors) specification. Contributions of any kind welcome!