Latest image broke the github actions android builds

It looks like the refactor in https://gitlab.com/gableroux/unity3d/-/commit/4d1eaa74cbec79386cda4f797e1db63ebcda1c20 and related commits broke the github action android builds. After an initial investigation, it looks like Unity is no longer able to find the Android Tools or the JDK.

The Android Tools issue looks like an easy fix and we just need to define the ANDROID_HOME variable again.

JDK appears a bit more complicated. I tried simply installing it the way it was done before but that didn't completely fix the issue. Defining a JAVA_HOME variable also didn't help. There's probably something silly I'm missing and hope to have more time to investigate soon but wanted to open this issue in case others are experiencing the same problem or if @szymon-kazmierczak or @gableroux have additional insights.

Additional context: https://github.com/webbertakken/unity-builder/pull/125