[DataGrid] Remove sortDirection from column definitions

[dtassone]

• [DataGrid] Remove sortDirection from column definitions. Consolidate around fewer ways of doing the same thing.

  -columns[1] = { ...columns[1], sortDirection: 'asc' };
  
  return (
    <div className="grid-container">
  -   <DataGrid rows={rows} columns={columns} />
  +   <DataGrid rows={rows} columns={columns} sortModel={[{field: columns[1].field, sort: 'asc'}]} />
    </div>

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fix #244