Fix the aria-label attrs in gr.Chatbot() (#6900)

* Fix the aria-label attrs in `gr.Chatbot()`

* add changeset

---------

Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Ali Abdalla <ali.si3luwa@gmail.com>

.changeset/happy-rooms-suffer.md

@@ -0,0 +1,6 @@
+---
+"@gradio/chatbot": minor
+"gradio": minor
+---
+
+feat:Fix the aria-label attrs in `gr.Chatbot()`

js/chatbot/shared/ChatBot.svelte

@@ -173,8 +173,14 @@
 									}}
 									dir={rtl ? "rtl" : "ltr"}
 									aria-label={(j == 0 ? "user" : "bot") +
-										"'s message:' " +
-										message}
+										"'s message: " +
+										(typeof message === "string"
+											? message
+											: `a file of type ${message.file?.mime_type}, ${
+													message.file?.alt_text ??
+													message.file?.orig_name ??
+													""
+											  }`)}
 								>
 									{#if typeof message === "string"}
 										<Markdown