Fix 04-create-server test to use a common prefix.

We need servers to dispose of for the 07-delete-server acceptance test.
Creating a bunch of servers in that test only to turn around and delete
them again will be unnecessarily time-consuming.  Instead, we'll use
ListServers() to discover a set of pre-existing servers to delete.
04-create-server already creates a batch, and will always execute before
07-delete-server (since 4 < 7).  Altering 04-create-server to put a tag
in the name of the servers it creates will allow 07-delete-server to
find them and delete them again.

The only exception is if any intervening tests fail.  You'll need to
clean up manually in that case.
2 files changed