add comments

pkg/validators/not_blank.go

@@ -6,6 +6,7 @@ import (
 	"github.com/go-playground/validator/v10"
 )
 
+// NotBlank returns whether the given content is not blank
 func NotBlank(fl validator.FieldLevel) bool {
 	if value, ok := fl.Field().Interface().(string); ok {
 		if value != "" && strings.Trim(value, " ") != "" {