Update macOS install instructions

Remove installing xcode command line tools, no longer necessary as installer doesn't require python
Update picture of extracted installer for new logo
Add picture of warning about downloaded files

source/docs/zero-to-robot/step-2/wpilib-setup.rst

@@ -56,12 +56,15 @@ When you download the WPILib installer, it is distributed as a disk image file `
    .. tab-item:: macOS
       :sync: macos
 
-      For this release, macOS users will need to have the Xcode Command Line Tools installed before running the installer; we are working on removing this requirement in a future release. This can be done by running ``xcode-select --install`` in the Terminal.
-
-      macOS users can double click on the downloaded ``DMG`` and then select ``WPILibInstaller`` to launch the application.
+      macOS users can double click on the downloaded ``dmg`` and then select ``WPILibInstaller`` to launch the application.
 
       .. image:: images/wpilib-setup/macos-launch.png
-         :alt: Show the macOS screen after double clicking the DMG file.
+         :alt: Show the macOS screen after double clicking the .dmg file.
+
+      If a warning is shown about WPILibInstaller being downloaded from the internet, select :guilabel:`Open`.
+
+      .. image:: images/wpilib-setup/macos-downloaded.png
+         :alt: Warning about WPILibInstaller being downloaded from the internet
 
    .. tab-item:: Linux
       :sync: linux