Update README.md

README.md

@@ -13,10 +13,6 @@
 
 <!-- ALL-CONTRIBUTORS-BADGE:END -->
 
-<div align="center">
-  <img width="auto" alt="Screen Shot 2021-11-19 at 4 59 21 PM" src="https://user-images.githubusercontent.com/17484350/229027815-eee0bf22-f3e5-444d-9d90-6409c68a0dc9.png">
-</div>
-
 ## changed-files
 
 Effortlessly track all changed files and directories relative to a target branch, preceding commit or the last remote commit returning **relative paths** from the project root using this GitHub action.
@@ -300,6 +296,9 @@ Support this project with a :star:
 |     U     |   Unmerged   |
 |     X     |   Unknown    |
 
+> **Warning**:
+> * When using `files_yaml*` ensure all ouputs are prefixed by the key. e.g. `test_added_files`, `test_any_changed`
+
 ## Outputs
 
 <!-- AUTO-DOC-OUTPUT:START - Do not remove or modify this section -->