Allow Dockerfile users to explicitly set the base image

ekcasey · ekcasey · commit 72ca379178ca · 2021-03-24T11:40:20.000-04:00
Stil defaults to ubuntu:bionic

Signed-off-by: Emily Casey &lt;ecasey@vmware.com&gt;
diff --git a/ci/Dockerfile b/ci/Dockerfile
@@ -1,4 +1,5 @@
-FROM ubuntu:bionic
+ARG base_image=ubuntu:bionic
+FROM ${base_image}
 
 RUN apt-get update && apt-get install -y \
     build-essential \
