Fix mag settings shortcut on secure screens (#20318)
Summary of the issue:
On secure screens, e.g. UAC screen, pressing NVDA+control+w reports "Action unavailable in secure context" instead of opening Magnifier settings.
Description of user facing changes:
Pressing NVDA+control+w on secure screens now opens Magnifier settings as expected.
Description of developer facing changes:
N/A
Description of development approach:
Removed the inappropriate @blockAction.when(blockAction.Context.SECURE_MODE) decorator.
