README.md: fix typo

README.md contains a minor typo that inaccurately describes MoiMoi's
behavior.

This needs to change to ensure that the user guide is consistent
with the chatbot's behavior.

Let's fix the typo.

This keeps the user guide clear and correct, providing a reliable
reference for users.

docs/README.md

@@ -9,7 +9,7 @@ If you're a fast typist, MoiMoi helps you manage tasks more quickly than traditi
 
 ## Getting started
 
-1. Ensure that Java 17 or above is installed in your computer.
+1. Ensure that Java 17 is installed in your computer.
 2. Download the jar file of the latest release, from [here](https://github.com/wkxcass/ip/releases/).
 3. Move the jar file into an empty folder.
 4. Open a command window in that folder (right-click on the folder, then select "Open in Terminal").