pybricks._common: Fix parameter name in LightMatrix.orientation().

The parameter `up` was named `top` here, which does not reflect the state of the current code.

See https://github.com/pybricks/pybricks-micropython/blob/master/pybricks/common/pb_type_lightmatrix.c#L59C25 for usage in the code itself.

Author: JoBeGaming

src/pybricks/_common.py

@@ -828,7 +828,7 @@ def orientation(self, up: Side) -> None:
         contents remain unchanged.
 
         Arguments:
-            top (Side): Which side of the light matrix display is "up" in your
+            up (Side): Which side of the light matrix display is "up" in your
                 design. Choose ``Side.TOP``, ``Side.LEFT``, ``Side.RIGHT``,
                 or ``Side.BOTTOM``.
         """