Remove duplicated test libraries in POM dependencies (#6430)

### Motivation
The removed test libraries were already defined in the parent pom

### Modification
Removed duplicated test libraries in POM dependencies
diff --git a/pulsar-io/hdfs2/pom.xml b/pulsar-io/hdfs2/pom.xml
index e7eedda..d6da9b4 100644
--- a/pulsar-io/hdfs2/pom.xml
+++ b/pulsar-io/hdfs2/pom.xml
@@ -46,11 +46,6 @@
     </dependency>
     
   	<dependency>
-  		<groupId>org.testng</groupId>
-  		<artifactId>testng</artifactId>
-  		<scope>test</scope>
-  	</dependency>
-  	<dependency>
   		<groupId>org.apache.hadoop</groupId>
   		<artifactId>hadoop-client</artifactId>
   		<version>2.8.2</version>
diff --git a/pulsar-io/hdfs3/pom.xml b/pulsar-io/hdfs3/pom.xml
index 1ceada4..40c8595 100644
--- a/pulsar-io/hdfs3/pom.xml
+++ b/pulsar-io/hdfs3/pom.xml
@@ -51,11 +51,6 @@
   		<version>3.1.1</version>
   	</dependency>
 
-  	<dependency>
-  		<groupId>org.testng</groupId>
-  		<artifactId>testng</artifactId>
-  		<scope>test</scope>
-  	</dependency>
   </dependencies>
   
   <build>
diff --git a/pulsar-io/mongo/pom.xml b/pulsar-io/mongo/pom.xml
index 6f764c2..877a29d 100644
--- a/pulsar-io/mongo/pom.xml
+++ b/pulsar-io/mongo/pom.xml
@@ -63,12 +63,6 @@
       <groupId>com.google.guava</groupId>
       <artifactId>guava</artifactId>
     </dependency>
-    <dependency>
-      <groupId>${project.parent.groupId}</groupId>
-      <artifactId>buildtools</artifactId>
-      <version>${project.parent.version}</version>
-      <scope>test</scope>
-    </dependency>
   </dependencies>
 
   <build>
diff --git a/pulsar-io/redis/pom.xml b/pulsar-io/redis/pom.xml
index deadbc3..4001fc9 100644
--- a/pulsar-io/redis/pom.xml
+++ b/pulsar-io/redis/pom.xml
@@ -76,12 +76,6 @@
             <version>3.2.2</version>
         </dependency>
         <dependency>
-            <groupId>${project.parent.groupId}</groupId>
-            <artifactId>buildtools</artifactId>
-            <version>${project.parent.version}</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
             <groupId>com.github.kstyrc</groupId>
             <artifactId>embedded-redis</artifactId>
             <version>0.6</version>