DOCS: Remove Stadia from Known Limitations page (#2206)

Author: JonMUnity

Packages/com.unity.inputsystem/Documentation~/KnownLimitations.md

@@ -27,7 +27,6 @@ The following is a list of known limitations that the Input System currently has
 * (Windows) Pen input will not work with Wacom devices if "Windows Ink" support is turned off.
 * (Windows) HID input is not currently supported in 32-bit players. This means that devices such as the PS4 controller will not work in 32-bit standalone players. Use the 64-bit standalone player instead.
 * (Android) We only support a single Touchscreen at the moment.
-* (Stadia) The Stadia controller is only supported __in__ the Stadia player at the moment. In the editor, use the generic `Gamepad` for bindings and use any Xbox or PS4 controller for testing.
 * Joy-Cons are only supported on Switch.
 * Sensors in the PS4 controller are currently only supported on PS4.
   >NOTE: Support for NDA platforms is distributed as separate packages due to licensing restrictions. The packages, at this point, are made available separately to licensees for download and installation.