fix import (#12529)

dolphinscheduler-alert/dolphinscheduler-alert-plugins/dolphinscheduler-alert-script/src/main/java/org/apache/dolphinscheduler/plugin/alert/script/ScriptSender.java

@@ -18,7 +18,8 @@
 package org.apache.dolphinscheduler.plugin.alert.script;
 
 import org.apache.dolphinscheduler.alert.api.AlertResult;
-import org.apache.dolphinscheduler.spi.utils.StringUtils;
+
+import org.apache.commons.lang3.StringUtils;
 
 import java.io.File;
 import java.util.Map;