fix(material/chips): add aria-hidden to host chip

add aria-hidden to host chip so Talkback ignores element

fixes b/286286473

Author: DBowen33

src/material/chips/chip.ts

@@ -87,6 +87,7 @@ export interface MatChipEvent {
     '[attr.role]': 'role',
     '[attr.tabindex]': '_getTabIndex()',
     '[attr.aria-label]': 'ariaLabel',
+    '[attr.aria-hidden]': 'true',
     '(keydown)': '_handleKeydown($event)',
   },
   encapsulation: ViewEncapsulation.None,