[Docs] Clean up docs/newbs_building_firmware.md (#6930)

* Clean up the blocks in the second section so that macOS & Windows are in the same block with the command

* As suggested by fauxpark

docs/newbs_building_firmware.md

@@ -8,15 +8,15 @@ If you have closed and reopened your terminal window since following the first p
 
 Start by navigating to the `keymaps` folder for your keyboard.
 
-?> If you are on macOS or Windows there are commands you can use to easily open the keymaps folder.
+If you are on macOS or Windows there are commands you can use to easily open the keymaps folder.
 
-?> macOS:
+### macOS:
 
-    open keyboards/<keyboard_folder>/keymaps
+``` open keyboards/<keyboard_folder>/keymaps ```
 
-?> Windows:
+### Windows:
 
-    start .\\keyboards\\<keyboard_folder>\\keymaps
+``` start .\\keyboards\\<keyboard_folder>\\keymaps ```
 
 ## Create a Copy Of The `default` Keymap