Fix broken apt dependencies in baseline.sh

Change-Id: I3d3c9ce5822c2d0fd5205086665eaaba9e0d79ef
diff --git a/packer/provision/baseline.sh b/packer/provision/baseline.sh
index c8a720d..168fd27 100644
--- a/packer/provision/baseline.sh
+++ b/packer/provision/baseline.sh
@@ -221,7 +221,9 @@
 
     echo "---> Updating operating system"
 
+    apt-get clean
     apt-get update -m
+    apt-get -f install || true # attempt to fix broken packages
     apt-get install -y software-properties-common apt-transport-https
 
     # add additional repositories