Increase number of forks by one

The vms running the bots seem to be under subscribed

Change-Id: I73eb62a704c2c8c1aa42bed3e9c75538bbba21b7
diff --git a/build.gradle b/build.gradle
index 364cb30..d7c59dd 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1763,7 +1763,7 @@
       maxParallelForks = processors.intdiv(userDefinedCoresPerFork.toInteger()) ?: 1
     } else {
       // On normal work machines this seems to give the best test execution time (without freezing)
-      maxParallelForks = processors.intdiv(3) ?: 1
+      maxParallelForks = (processors.intdiv(3) ?: 1) + 1
     }
     println("NOTE: Max parallel forks " + maxParallelForks)