Fix maven path.

Change-Id: I252d7a644a9e4064a9f1a816a2be3f25f37b4c43
diff --git a/protoc-artifacts/Dockerfile b/protoc-artifacts/Dockerfile
index 8ed87c9..5143b02 100644
--- a/protoc-artifacts/Dockerfile
+++ b/protoc-artifacts/Dockerfile
@@ -23,7 +23,7 @@
 # Install Maven
 RUN wget -q http://apache.cs.utah.edu/maven/maven-3/3.3.9/binaries/apache-maven-3.3.9-bin.tar.gz -O - | \
     tar xz -C /var/local
-ENV PATH /var/local/apache-maven-3.3.3/bin:$PATH
+ENV PATH /var/local/apache-maven-3.3.9/bin:$PATH
 
 # Install GCC 4.7 to support -static-libstdc++
 RUN wget http://people.centos.org/tru/devtools-1.1/devtools-1.1.repo -P /etc/yum.repos.d