Create a server in resource_setup in ImagesOneServerTestJSON

Generally speaking resources are better not to be shared between
testcases, but testcases in ImagesOneServerTestJSON can share
one server because they have almost no effect on the server,
thus we can reduce the time of creating one server.

Change-Id: I16a786ad874bd7d85c0a517a6f7d7c16655a6234
1 file changed