fix(ui) Fix tags and terms columns on nested schema fields

[chriscollins3456]

When we updated ant design, I believe they introduced a new bug where the rowIndex for nested table rows is inconsistent depending on the method you're using. The onCell function gives the overall index as if it were a flat list of rows while the render method gives the index of the row in the nested field context (this is not how it used to work).

Therefore, the tagHoveredIndex piece of state would never line up with the row and it would never think you're hovering over it so we would never show the option to add tags and terms. Since fieldPath is unique in a schema anyways, we don't need the rowIndex here so I simply remove it.

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