Function insert_rows 

pub fn insert_rows(
    ws: &mut WorksheetXml,
    start_row: u32,
    count: u32,
) -> Result<()>

Insert count empty rows starting at start_row, shifting existing rows at and below start_row downward.

Cell references inside shifted rows are updated so that e.g. “B5” becomes “B8” when 3 rows are inserted at row 5.