REPORT-65192 公式合法性检测错误字符位置返回不正确

1.处理一下极少出现的情况，默认返回0的位置吧。

designer-base/src/main/java/com/fr/design/formula/exception/function/FormulaCheckWrongFunction.java

@@ -73,6 +73,8 @@ public class FormulaCheckWrongFunction implements Function<Exception, FormulaChe
         if (invalidFormula.contains(",")) {
             invalidFormula = invalidFormula.substring(0, invalidFormula.indexOf(","));
         }
-        return formulaText.indexOf(invalidFormula);
+        int index = formulaText.indexOf(invalidFormula);
+        return Math.max(index, 0);
     }
+
 }