[macOS] Enabled secure restorable state.

(cherry picked from commit 84380a94f7)

platform/osx/os_osx.mm

@@ -168,6 +168,10 @@ static NSCursor *cursorFromSelector(SEL selector, SEL fallback = nil) {
 
 @implementation GodotApplicationDelegate
 
+- (BOOL)applicationSupportsSecureRestorableState:(NSApplication *)app {
+	return YES;
+}
+
 - (void)forceUnbundledWindowActivationHackStep1 {
 	// Step 1: Switch focus to macOS SystemUIServer process.
 	// Required to perform step 2, TransformProcessType will fail if app is already the in focus.