Operators greaterThanOrEqual and lessThanOrEqual are not taken into account in ConditionalFormat for cell type

[echarlus]

When setting up conditional format for type "cell" and using a >= or <= criteria, the value parameter is not taken into account and therefore the conditional style does not work

Steps to reproduce the issue:

1. Create a conditional style format like this :
   if pctOKStyle, err = cg.workbook.NewConditionalStyle({"font":{"bold":true, "color":"#38761D"}}); err != nil {
   log.Printf("Failed to create OKStyle : %v", err)
   }
   if pctNOKStyle, err = cg.workbook.NewConditionalStyle({"font":{"color":"#FF9900"}}); err != nil {
   log.Printf("Failed to create NOKStyle : %v", err)
   }
   pctFormat := fmt.Sprintf([{"type":"cell","criteria":">","format":%d,"value":"0"},{"type":"cell","criteria":"<=","format":%d,"value":"0"}], pctNOKStyle, pctOKStyle)

if err := workbook.SetConditionalFormat(detailsSheet, "A1:A38"), pctFormat); err != nil {
log.Printf("Failed to set conditional format on col %s : %v", c, err)
}

Describe the results you received:
for cells with values <=0 , the font color is not changed

Describe the results you expected:

One should see orange font when cell value is >0 and green font when <=0
However, the green format is never applied

Output of go version:
go version go1.14.1 darwin/amd64

Excelize version or commit ID:
Commit ID:
66d0272

Environment details (OS, Microsoft Excel™ version, physical, etc.):
Mac OS 10.15.4 / Excel 16.16.20