Border Style for DiagonalDown and DiagonalUp in cell styles was not applied correctly.

(cherry picked from commit ab735d6)

Author: Claudia Beatriz Murialdo Garrone

dotnet/src/dotnetframework/GxOffice/poi/xssf/ExcelCells.cs

@@ -1117,7 +1117,7 @@ private XSSFCellStyle ApplyNewCellStyle(XSSFCellStyle cellStyle, ExcelStyle newC
 					CT_Xf _cellXf = cellStyle.GetCoreXf();
 					ExcelBorder border = (hasDiagonalUp) ? cellBorder.BorderDiagonalUp : cellBorder.BorderDiagonalDown;
 					XSSFColor diagonalColor = ToColor(border.BorderColor);
-					BorderStyle.TryParse(border.Border, out BorderStyle borderStyle);
+					BorderStyle borderStyle = ConvertToBorderStyle(border.Border);
 					SetBorderDiagonal(borderStyle, diagonalColor, this.pWorkbook.GetStylesSource(), _cellXf, hasDiagonalUp, hasDiagonalDown);
 				}
 			}