Fix botched gocovmerge vendoring

Signed-off-by: Joffrey F <joffrey@docker.com>

Author: shin-

Gopkg.lock

@@ -22,7 +22,6 @@
 
 required = ["github.com/wadey/gocovmerge"]
 
-
 [[constraint]]
   name = "github.com/spf13/cobra"
   version = "0.0.2"
@@ -45,10 +44,6 @@ required = ["github.com/wadey/gocovmerge"]
   name = "github.com/gotestyourself/gotestyourself"
   branch = "master"
 
-[[constraint]]
-  name = "github.com/wadey/gocovmerge"
-  branch = "master"
-
 [[constraint]]
   name = "github.com/sirupsen/logrus"
   version = "v1.0.5"
@@ -81,6 +76,10 @@ required = ["github.com/wadey/gocovmerge"]
   name = "google.golang.org/grpc"
   revision = "v1.3.0"
 
+[[constraint]]
+  name = "github.com/wadey/gocovmerge"
+  branch = "master"
+
 [prune]
   non-go = true
   unused-packages = true