add test case

sharding-core/pom.xml

@@ -87,15 +87,5 @@
             <groupId>ch.qos.logback</groupId>
             <artifactId>logback-classic</artifactId>
         </dependency>
-        <dependency>
-            <groupId>org.powermock</groupId>
-            <artifactId>powermock-module-junit4</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.powermock</groupId>
-            <artifactId>powermock-api-mockito2</artifactId>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 </project>