Fix numbered bullets

One step was removed, so had to update the numbered bullets on Goose Desktop instructions.

Author: dprevoznik

reference/mcp-server.mdx

@@ -128,13 +128,13 @@ Click [here](goose://extension?cmd=npx&arg=-y&arg=mcp-remote&arg=https%3A%2F%2Fm
 
 1. Click `Extensions` in the sidebar of the Goose Desktop.
 2. Click `Add custom extension`.
-4. On the `Add custom extension` modal, enter:
+3. On the `Add custom extension` modal, enter:
    - **Extension Name**: `Kernel`
    - **Type**: `STDIO`
    - **Description**: `Access Kernel's cloud-based browsers via MCP`
    - **Command**: `npx -y mcp-remote https://mcp.onkernel.com/mcp`
    - **Timeout**: `300`
-5. Click `Save Changes` button.
+4. Click `Save Changes` button.
 
 ### Goose CLI