ocaml-zarith-1.13-bp156.1.3

- Remove usage of dune.configurator because ocamlfind names which
  contain a dot are not considered valid anymore with dune 3.13

- Update to version 1.13
  See included Changes for details

- Upgrade to version 1.12
  * PR #79: fast path in OCaml (instead of assembly language)
  * PR #94: remove source preprocessing and simplify configuration
  * PR #93: fix parallel build
  * PR #92: fix benchmark for subtraction

- Initial version 1.11