Update to MyBatis 3.4.4

Fix gh-191

Author: kazuki43zoo

pom.xml

@@ -113,7 +113,7 @@
     <dependency>
       <groupId>org.mybatis</groupId>
       <artifactId>mybatis</artifactId>
-      <version>3.4.2</version>
+      <version>3.4.4</version>
       <scope>provided</scope>
     </dependency>