cluster/clustercfg: fix BUILD

This is continued fallout after migrating from rules_pip.

Change-Id: Idb9b4d4f22aa36512d220ac31375bae7a0f25e4e
diff --git a/cluster/clustercfg/BUILD b/cluster/clustercfg/BUILD
index d83a921..433f79c 100644
--- a/cluster/clustercfg/BUILD
+++ b/cluster/clustercfg/BUILD
@@ -9,8 +9,11 @@
     ],
     visibility = ["//visibility:public"],
     deps = [
-        requirement("fabric"),
         requirement("asn1crypto"),
+        requirement("cffi"),
+        requirement("fabric"),
+        requirement("idna"),
+        requirement("six"),
         "//tools:secretstore_lib",
     ],
 )