feat(css): add new display classes (#30055)

Issue number: internal

---------

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## What is the new behavior?
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this PR. -->

- Add new display-contents and display-flex classes.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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core/src/css/display.scss

@@ -5,6 +5,14 @@
 // --------------------------------------------------
 // Modifies display of a particular element based on the given classes
 
+.ion-display-flex {
+  display: flex !important;
+}
+
+.ion-display-contents {
+  display: contents !important;
+}
+
 .ion-hide {
   display: none !important;
 }