Add subagent tests

Change-Id: I331dd0cb8805b54384923ff305bfc6f3406de4d8
diff --git a/server/tests/.testignore b/server/tests/.testignore
new file mode 100644
index 0000000..e96d735
--- /dev/null
+++ b/server/tests/.testignore
@@ -0,0 +1 @@
+# This directory contains standalone test executables, not Go tests
\ No newline at end of file