Updated README.md file of the hello_world example (#64766)

diff --git a/examples/hello_world/README.md b/examples/hello_world/README.md
index 6715517..0a9132c 100644
--- a/examples/hello_world/README.md
+++ b/examples/hello_world/README.md
@@ -1,7 +1,8 @@
+## To run the Hello World demo:
 ```
-# To run the Hello World demo:
 flutter run
-
-# To run the Hello World demo showing Arabic:
+```
+## To run the Hello World demo showing Arabic:
+```
 flutter run lib/arabic.dart
 ```