ADD：操作文档

controllers/sales.go

@@ -196,7 +196,7 @@ func (c SalesController) SalesReportExcel() {
 			Font:      &excelize.Font{Bold: true, Size: 20, Family: "宋体"},
 			Alignment: &excelize.Alignment{Horizontal: "center", Vertical: "center"},
 		})
-	f.MergeCell("Sheet1", "A1", "J1")
+	f.MergeCell("Sheet1", "A1", "G1")
 	f.SetRowStyle("Sheet1", 1, 1, StyleTitle)
 	f.SetRowHeight("Sheet1", 1, 50)
 	var interval string