We have ~20 test jenkins builds are running against various GCI image, and Kubernetes builds already. @wonderfly kindly agreed to add another one to test docker nightly build for us. This is relatively easy comparing to today's debian-based containerVM image, and less error-prone.

@liangchenye This is the first step to unblock the work of automating docker validation process which you have been working on. Beyond this, you need to:

• Introduce node e2e test suite for automating docker validation. You can re-use the cloud_init config introduced by @wonderfly
• Include your runtime conformance test suites to the newly introduced docker validation suite.
• Convert our current docker performance tests written by @Random-Liu to the new test suite.
• Add docker restart / recovery, resource tracking tests.

After the first suite is done, we can expand the test suite to cover other os distro easily.