ci: exit with same status as xcodebuild (#2352)
ci: exit with same status as xcodebuild (#2352)

* CI systems usually use status codes to determine if the build has failed. When used with xcpretty it always returns zero.
couchbase/couchbase-lite-ios,couchbase/couchbase-lite-ios,couchbase/couchbase-lite-ios,couchbase/couchbase-lite-ios,couchbase/couchbase-lite-ios,couchbase/couchbase-lite-ios