add notice of ui interference to ui automator readme

PiperOrigin-RevId: 591124208
diff --git a/README.md b/README.md
index 6b32037..4ed35c5 100644
--- a/README.md
+++ b/README.md
@@ -72,6 +72,9 @@
 
 ## Notice
 
+*   While UI Automation is processing, interfering android phone with any UI
+    operation might fail the autoation.
+
 ## Report issue
 
 -   Click