tests: Add test-pull-bareuseronly
I was going to fix a bug in the static deltas code and I noticed
we were missing `pull-test.sh` coverage for bareuseronly.
Obviously fixing this requires duplicating some of the bits we have in
`basic-test.sh`; need to hoist that into `libtest.sh`. For now though let's get
the coverage.
Closes: #1270
Approved by: jlebon
Origin: upstream, 2017.13, commit:
95afe2848d65a8062f4a76adb1ab80b6bcc4d79e
Gbp-Pq: Topic 2017.13
Gbp-Pq: Name tests-Add-test-pull-bareuseronly.patch