Validate project refs vs. global-refdb in parallel

Change-Id: I3ddc8c40a6fa8a4e8151294dad95881eee2d6d37

multi-primary/globalrefdb.groovy

diff --git a/multi-primary/globalrefdb.groovy b/multi-primary/globalrefdb.groovy
index 8b79239..93ae9c6 100644
--- a/multi-primary/globalrefdb.groovy
+++ b/multi-primary/globalrefdb.groovy
@@ -81,7 +81,7 @@
           def refsDone = 0
           def refsDonePerc = 0
           def startTime = System.currentTimeMillis()
-          repo.refDatabase.refs.each { ref ->
+          repo.refDatabase.refs.parallelStream().forEach { ref ->
             def refUpToDate = checkRef(projectName, repo, ref)
             upToDate = upToDate && refUpToDate
             if (!verbose) {