fix(tabs): override browser focus styles in tab content container (#8343)

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

Author: emyarod

packages/components/src/components/tabs/_tabs.scss

@@ -402,6 +402,10 @@
   //-----------------------------
   .#{$prefix}--tab-content {
     padding: $carbon--spacing-05;
+
+    &:focus {
+      @include focus-outline('outline');
+    }
   }
 
   //-----------------------------