fix 修复 splitTo 转换后的list包含null问题

ruoyi-common/ruoyi-common-core/src/main/java/org/dromara/common/core/utils/StringUtils.java

@@ -318,6 +318,7 @@ public class StringUtils extends org.apache.commons.lang3.StringUtils {
             .stream()
             .filter(Objects::nonNull)
             .map(mapper)
+            .filter(Objects::nonNull)
             .collect(Collectors.toList());
     }