Bump hadoop-client from 2.0.0-cdh4.7.0 to 2.7.0 in /hdfs-sink

Bumps hadoop-client from 2.0.0-cdh4.7.0 to 2.7.0.

---
updated-dependencies:
- dependency-name: org.apache.hadoop:hadoop-client
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

hdfs-sink/pom.xml

@@ -56,7 +56,7 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <hadoop.version>2.0.0-cdh4.7.0</hadoop.version>
+        <hadoop.version>2.7.0</hadoop.version>
         <maven.test.skip>true</maven.test.skip>
     </properties>