Maven must run in batch mode when listing staged releases
Maven must run in batch mode when listing staged releases

Motivation:
We're grepping the output of the command, and terminal color codes get in the way of that.

Modification:
Ask maven to run in batch mode, to prevent colored output.

Result:
The list_staged_release.sh script no longer fails to find any staged releases in the maven output.

netty/netty,netty/netty,netty/netty,netty/netty,netty/netty