After initial investigation, it seems 4d1eaa74cb and related commits broke the unity-builder android builds. Unity is no longer able to find the Android Tools or the JDK.
I was able to modify the Dockerfile to export an `ANDROID_HOME` env variable to get past the first issue but so far haven't found how to configure the Unity JDK location. Setting a `JAVA_HOME` env variable doesn't seem to help.
Until we find a fix upstream (https://gitlab.com/gableroux/unity3d), pinning to an older version of the unity-3d image. We probably don't want to merge this since the image hash isn't going to work on all platforms.
Benoit Dion
Webber