Add warning about reanalyze development to README #235

Job	Run time
build (macos-13, rescript)	12m 25s
build (macos-14, rescript)	6m 51s
build (ubuntu-latest, rescript)	6m 7s
build (windows-latest, rescript)	11m 34s
build (ubuntu-latest, ocaml.4.08, 4.08.x, opam exec -- dune build)	6m 8s
build (ubuntu-latest, ocaml.4.14, 4.14.x, opam exec -- dune build)	6m 7s
build (ubuntu-latest, ocaml.5.0, 5.0.x, opam exec -- dune build)	6m 21s
build (ubuntu-latest, ocaml.5.1, 5.1.x, opam exec -- dune build)	6m 3s
build (ubuntu-latest, ocaml.5.2, 5.2.x, opam exec -- dune build)	6m 15s
npm_pack	19s
	1h 8m 10s

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