fix: tensorflow/java/maven/tensorflow-hadoop/pom.xml to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JAVA-COMGOOGLEGUAVA-1015415
- https://snyk.io/vuln/SNYK-JAVA-COMGOOGLEGUAVA-32236
- https://snyk.io/vuln/SNYK-JAVA-COMJCRAFT-30302
- https://snyk.io/vuln/SNYK-JAVA-COMMONSCODEC-561518
- https://snyk.io/vuln/SNYK-JAVA-COMMONSCOLLECTIONS-30078
- https://snyk.io/vuln/SNYK-JAVA-COMMONSCOLLECTIONS-472711
- https://snyk.io/vuln/SNYK-JAVA-COMMONSIO-1277109
- https://snyk.io/vuln/SNYK-JAVA-IONETTY-30430
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHECOMMONS-32473
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHADOOP-30627
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHADOOP-30628
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHADOOP-30634
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHADOOP-31587
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHADOOP-461004
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHTTPCOMPONENTS-1048058
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHTTPCOMPONENTS-30646
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHTTPCOMPONENTS-31517
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEHTTPCOMPONENTS-451097
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEZOOKEEPER-174781
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEZOOKEEPER-31035
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEZOOKEEPER-31428
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHEZOOKEEPER-32301

tensorflow/java/maven/tensorflow-hadoop/pom.xml

@@ -14,7 +14,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.source>1.6</maven.compiler.source>
         <maven.compiler.target>1.6</maven.compiler.target>
-        <hadoop.version>2.6.0</hadoop.version>
+        <hadoop.version>3.3.1</hadoop.version>
         <protobuf.version>3.5.1</protobuf.version>
         <junit.version>4.11</junit.version>
     </properties>