CORD-2238: unit tests for vnaas syncsteps

Change-Id: Ic06b72ddd6d8934dfe0cd56e4d8386eccff19ccf
(cherry picked from commit b3a355468615d9a6eed596a0c698d97856abea98)
diff --git a/xos/synchronizer/steps/test_private_key b/xos/synchronizer/steps/test_private_key
new file mode 100644
index 0000000..3cb08a3
--- /dev/null
+++ b/xos/synchronizer/steps/test_private_key
@@ -0,0 +1 @@
+some_key