fix(SafeAreas): fix iOS fallback (#29941)

Issue number: internal

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- fix ion-statusbar css var fallback;


## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->
- CSS var --ion-statusbar-padding was not working because the Sass
variable was not escaped.


## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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core/src/css/ionic/core.ionic.scss

@@ -223,7 +223,7 @@ ion-toast-controller,
 
 html.plt-ios.plt-hybrid,
 html.plt-ios.plt-pwa {
-  --ion-statusbar-padding: globals.$ionic-space-m;
+  --ion-statusbar-padding: #{globals.$ionic-space-500};
 }
 
 @supports (padding-top: 20px) {