fix-alt-text-prompt-experiment: minor prompt improvement

Author: Igor Grubic

static/prompts/image-alt-text.prompt

@@ -30,4 +30,4 @@ Your response must be a valid JSON object using the following structure:
 
 ### Task:
 Given the following list of images: {{images}}, suggest a description for the alt attribute of each image that is helpful for the user.
-Use the base64 blob provided if the image is not supported by Firefall.
+Use the base64 blob provided if the image format is not supported.