Update introduction.mdx

Author: simoninithomas

units/en/unit0/introduction.mdx

@@ -36,6 +36,19 @@ Don’t forget to **<a href="http://eepurl.com/ic5ZUD">sign up to the course</a>
 
 Sign up  👉 <a href="http://eepurl.com/ic5ZUD">here</a>
 
+## Course Maintenance Notice 🚧
+
+Please note that this **Deep Reinforcement Learning course is now in a low-maintenance state**. However, it **remains an excellent resource to learn both the theory and practical aspects of Deep Reinforcement Learning**.
+
+Keep in mind the following points:
+
+- *Unit 7 (AI vs AI)* : This feature is currently non-functional. However, you can still train your agent to play soccer and observe its performance.
+
+- *Leaderboard* : The leaderboard is no longer operational.
+
+Aside from these points, all theory content and practical exercises remain fully accessible and effective for learning.
+
+If you have any problem with one of the hands-on **please check the issue sections where the community give some solutions to bugs**.
 
 ## What does the course look like? [[course-look-like]]
 
@@ -124,13 +137,6 @@ In this new version of the course, you have two types of challenges:
 
 <img src="https://huggingface.co/datasets/huggingface-deep-rl-course/course-images/resolve/main/en/unit0/challenges.jpg" alt="Challenges" width="100%"/>
 
-## I found a bug, or I want to improve the course [[contribute]]
-
-Contributions are welcomed 🤗
-
-- If you *found a bug 🐛 in a notebook*, please <a href="https://github.com/huggingface/deep-rl-class/issues">open an issue</a> and **describe the problem**.
-- If you *want to improve the course*, you can <a href="https://github.com/huggingface/deep-rl-class/pulls">open a Pull Request.</a>
-
 ## I still have questions [[questions]]
 
 Please ask your question in our <a href="https://discord.gg/ydHrjt3WP5">discord server #rl-discussions.</a>