Update signals.rst and instancing.rst (#7792)

* Update signals.rst

* Update signals.rst

Ctrl + Cmd + 1 on macOS

* Update instancing.rst

- Keyboard shortcut guidelines
- For combinations, use the + symbol with a space on either side of the symbol.

getting_started/step_by_step/instancing.rst

@@ -91,7 +91,7 @@ Click on it and drag it towards the center of the view.
 Play the game by pressing :kbd:`F5` (:kbd:`Cmd + B` on macOS). You should see it fall.
 
 Now, we want to create more instances of the Ball node. With the ball still
-selected, press :kbd:`Ctrl-D` (:kbd:`Cmd-D` on macOS) to call the duplicate
+selected, press :kbd:`Ctrl + D` (:kbd:`Cmd + D` on macOS) to call the duplicate
 command. Click and drag to move the new ball to a different location.
 
 .. image:: img/instancing_ball_duplicated.png

getting_started/step_by_step/signals.rst

@@ -239,7 +239,7 @@ Let's use a different node here. Godot has a :ref:`Timer <class_Timer>` node
 that's useful to implement skill cooldown times, weapon reloading, and more.
 
 Head back to the 2D workspace. You can either click the "2D" text at the top of
-the window or press :kbd:`Ctrl + F1` (:kbd:`Alt + 1` on macOS).
+the window or press :kbd:`Ctrl + F1` (:kbd:`Ctrl + Cmd + 1` on macOS).
 
 In the Scene dock, right-click on the Sprite2D node and add a new child node.
 Search for Timer and add the corresponding node. Your scene should now look like