Rename height to scale for openConsole() (#5139)

For Game::openConsole() and GUIChatConsole::openConsole() the
parameter name 'height' is misleading because it's actually a
percentage of the screen/window height.

src/guiChatConsole.h

@@ -41,7 +41,7 @@ class GUIChatConsole : public gui::IGUIElement
 	// Open the console (height = desired fraction of screen size)
 	// This doesn't open immediately but initiates an animation.
 	// You should call isOpenInhibited() before this.
-	void openConsole(f32 height);
+	void openConsole(f32 scale);
 
 	bool isOpen() const;