Update apps/site/pages/en/learn/command-line/how-to-read-environment-variables-from-nodejs.md

Co-authored-by: Augustin Mauroy <97875033+AugustinMauroy@users.noreply.github.com>
Signed-off-by: YCM Jason <me@ycmjason.com>

Author: ycmjason

apps/site/pages/en/learn/command-line/how-to-read-environment-variables-from-nodejs.md

@@ -75,7 +75,7 @@ Because this method is invoked post-initialization, the setting of startup-relat
 
 ### Example
 
-```env
+```txt
 PORT=1234
 ```