Removes Slf4j adapter which is no longer needed

Author: linghengqian

pom.xml

@@ -126,13 +126,6 @@
             <scope>test</scope>
             <optional>true</optional>
         </dependency>
-        <dependency>
-            <groupId>org.slf4j</groupId>
-            <artifactId>slf4j-nop</artifactId>
-            <version>${slf4j.version}</version>
-            <scope>test</scope>
-            <optional>true</optional>
-        </dependency>
         <dependency>
             <groupId>com.zaxxer</groupId>
             <artifactId>HikariCP</artifactId>