Add apt update before installing git

Author: camspec

docs/src/content/docs/start-here/initial-setup.mdx

@@ -25,9 +25,10 @@ Follow Microsoft's official guide to install WSL: https://learn.microsoft.com/en
 
 <Steps>
 1. Ensure you have Git installed. If you are using Ubuntu 24.04 LTS or later, or installed the default WSL distribution, you should already have it installed.
-If not, open a terminal and run the following command to install Git:
+If not, open a terminal and run the following commands to install Git:
 
     ```shell
+    sudo apt update
     sudo apt install git
     ```