VAP-4768 Added supported file formats (#262)

Author: ramsrib

fern/knowledge-base/knowledge-base.mdx

@@ -41,6 +41,10 @@ There are two main approaches to creating a Knowledge Base in Vapi:
 3. Select files in supported formats (`.txt`, `.pdf`, `.docx`, etc.)
 4. Wait for the upload to complete - you'll see your files listed in the Files section
 
+<Info>
+  Vapi supports various file formats for Knowledge Bases including: .txt, .pdf, .docx, .doc, .csv, .md, .tsv, .yaml, .json, .xml, and .log files.
+</Info>
+
 <Frame caption="Adding files to your Knowledge Base">
   <img
     src="../static/images/knowledge-base/files.png"