Fix T85363: Cmd + Tab shortcut overridden on macOS

Adds an exception so that the key-binding `control + Tab` does not get
duplicated as `command + Tab` on macOS because this is a global system
shortcut for the app switcher.

The key-binding `command + Tab` was shown for the operators “Toggle
Graph Editor“ and “Toggle Dope Sheet” in Dope Sheet and Graph Editor,
but only `control + Tab` actually worked.

Differential Revision: https://developer.blender.org/D10304

release/scripts/modules/bl_keymap_utils/platform_helpers.py

@@ -49,6 +49,7 @@ def keyconfig_data_oskey_from_ctrl_for_macos(keyconfig_data_src):
                     'W',
                     'ACCENT_GRAVE',
                     'PERIOD',
+                    'TAB',
             }):
                 if (not item_event.get("alt")) and (not item_event.get("shift")):
                     return False