change scala version to 2.11.12

Author: HmhWz

pom.xml

@@ -44,7 +44,7 @@
     <properties>
         <dss.version>1.0.1</dss.version>
         <linkis.version>1.0.3</linkis.version>
-        <scala.version>2.12.10</scala.version>
+        <scala.version>2.11.12</scala.version>
         <jdk.compile.version>1.8</jdk.compile.version>
         <maven.version>3.3.3</maven.version>
         <gson.version>2.8.5</gson.version>