Add rbm to /etc/hosts

This happens when compiling Android Components 102:

FAILURE: Build failed with an exception.

* What went wrong:
java.net.UnknownHostException: rbm: rbm: Temporary failure in name resolution
> rbm: rbm: Temporary failure in name resolution

Adding rbm to /etc/hosts solves the problem in the debug shell, but I think we should do that by default in all containers.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information