Add tests execution time to renode.md
diff --git a/tensorflow/lite/micro/docs/renode.md b/tensorflow/lite/micro/docs/renode.md
index 06daa78..f20611f 100644
--- a/tensorflow/lite/micro/docs/renode.md
+++ b/tensorflow/lite/micro/docs/renode.md
@@ -55,6 +55,7 @@
 
  * This makes use of the robot framework from Renode.
  * Note that the tests can currently not be run in parallel.
+ * It takes about 25 second to complete all tests, including around 3 seconds for suite startup/teardown and average 0.38 second per test.
 
 ## Under the hood of the Testing Infrastructure