Adds commons logging as a test dependency.

spring-cloud-zookeeper-discovery/pom.xml

@@ -98,6 +98,11 @@
 			<artifactId>feign-core</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>commons-logging</groupId>
+			<artifactId>commons-logging</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-web</artifactId>