Add 'linux' formula to dependency list

Change-Id: If5f6a583b1ff36c60de43a5c5c316d1d7375c5bf
Closes-Bug: PROD-12752
diff --git a/metadata.yml b/metadata.yml
index 390deb6..c087021 100644
--- a/metadata.yml
+++ b/metadata.yml
@@ -1,3 +1,6 @@
 name: "python"
 version: "0.2"
 source: "https://github.com/tcpcloud/salt-formula-python"
+dependencies:
+- name: linux
+  source: "https://github.com/salt-formulas/salt-formula-linux"