test: add missing dependency (#1248)

Signed-off-by: Rudi Grinberg <me@rgrinberg.com>

Author: rgrinberg

ocaml-lsp-server/test/e2e-new/dune

@@ -13,6 +13,7 @@
    %{bin:ocamlformat-rpc}
    for_ppx.ml
    for_pp.ml
+   for_pp.sh
    (package ocaml-lsp-server)))
  (libraries
   stdune