Fix builder error

We need to first populate the apt sources before installing anything. It was working on my machine because the layer was cached. After I purged all images I was able to replicate the same error message.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=251918035

release/builder/build.sh

@@ -14,10 +14,10 @@
 # limitations under the License.
 
 set -e
+apt-get update -y
 apt-get install locales -y
 locale-gen en_US.UTF-8
 apt-get install apt-utils -y
-apt-get update -y
 apt-get upgrade -y
 # Install Java
 apt-get install openjdk-8-jdk-headless -y