Add Director.ShardParam to the hash for a VCL spec.

pkg/varnish/vcl/spec.go

@@ -145,6 +145,7 @@ func (dir Director) hash(hash hash.Hash) {
 	binary.BigEndian.PutUint64(wBytes, w64)
 	hash.Write(wBytes)
 	hash.Write([]byte{byte(dir.Type)})
+	hash.Write([]byte(dir.ShardParam))
 }
 
 // NameTTLFrom is a enumeration of the ways that the name TTL that was