Duplicate random data causing intermittent Table test fail

[levithomason]

The table column test ensures there are no columns present for the TableColumn that was removed from the table definition. However, sometimes, there are two columns with the same name generated. Removing one, and testing that all are not present fails.

Instead, get a unique list of table columns before continuing.

In table test:

  describe('row', () => {
    it('only contains cells that were defined in TableColumns', () => {
      render(
        <Table data={tableData}>
          <TableColumn dataKey={randomDataKey} />
        </Table>
      )
...

[levithomason]

Fixed in #90