Give a test a real name in order to avoid including a port number in
the results summary file - which makes comparing test results between
runs hard.
gdb/testsuiteChangeLog:
* gdb.server/multi-ui-errors.exp: Give a test a real name to avoid
including a port number in the output.
Change-Id: I19334e176ac15aee2a9732a6060c58153d9fb793