CORD-2238 unit tests for veg syncsteps

Change-Id: I05e3360f61fdd6248a8538e88a2f68693e858230
(cherry picked from commit 60671dcbf9f44605bf7378373a9bbf844a60a5c5)
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