Dynamically determine image architecture

The image architecture is currently hardcoded, this patch removes
that hardcoded value to allow for ARM64 builds to go through.

Change-Id: I214208421dd2b1d641166f0cfd977cf33073dc7a
Issue-ID: CIMAN-154
Signed-off-by: Mohammed Naser <mnaser@vexxhost.com>
diff --git a/src/main/docker/Dockerfile b/src/main/docker/Dockerfile
index 6fac6e2..362814d 100644
--- a/src/main/docker/Dockerfile
+++ b/src/main/docker/Dockerfile
@@ -10,7 +10,7 @@
 ## sudo -E is required to preserve the environment. If you remove that line, it will most like freeze at this step
 RUN sudo -E add-apt-repository ppa:openjdk-r/ppa && apt-get update && apt-get install -y openjdk-8-jdk
 ## Setup JAVA_HOME, this is useful for docker commandline
-ENV JAVA_HOME usr/lib/jvm/java-8-openjdk-amd64
+ENV JAVA_HOME usr/lib/jvm/java-8-openjdk-$(dpkg --print-architecture)
 RUN export JAVA_HOME
 
 # Build up the deployment folder structure