missing include

Former-commit-id: 06f39cb05b607c8744297dc8423603523cea382a

include/igl/edges_to_path.cpp

@@ -1,6 +1,6 @@
 #include "edges_to_path.h"
 #include "ismember.h"
-#include "adjacency_matrix.h"
+#include "adjacency_list.h"
 
 template <
   typename DerivedE,