fix(data-table): center align checkboxes (#11743)

### Related Ticket(s)

Closes #11742

### Description

This PR center aligns data table checkboxes within their flexbox divs in order to avoid reliance on inconsistent `vertical-align` implementations across various browsers

### Changelog

**New**

- data table checkbox flexbox alignment rule

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packages/carbon-web-components/src/components/data-table/_table-core.scss

@@ -223,6 +223,7 @@
   .#{$prefix}--table-column-checkbox div,
   .#{$prefix}--table-expand div {
     display: flex;
+    align-items: center;
     block-size: 100%;
   }
 }