Update C# Rider install steps for now built-in plugin "Godot Support" (#10323)

* Plugin now bundled with rider so can't be installed

As of Rider 2024.2 the plugin is bundled with the software and can't be installed which can be confusing.
https://plugins.jetbrains.com/plugin/13882-godot-support

---------

Co-authored-by: tetrapod <[email protected]>

Author: RB35

tutorials/scripting/c_sharp/c_sharp_basics.rst

@@ -90,7 +90,7 @@ In Godot's **Editor → Editor Settings** menu:
 In Rider:
 
 - Set **MSBuild version** to **.NET Core**.
-- Install the **Godot support** plugin.
+- If you are using a Rider version below 2024.2, install the **Godot support** plugin. This functionality is now built into Rider.
 
 Visual Studio Code
 ~~~~~~~~~~~~~~~~~~