pkg: build and make ocamlformat dev-tool available #28077

Job	Run time
Coverage (4.14.x)	9m 40s
Build microbenchmarks	5m 12s
Coq 8.16.1	8m 37s
Build (macos-latest, 4.14.x)	14m 56s
Build (ubuntu-latest, 4.14.x)	8m 44s
Create local opam switch (macos-latest, 5)	7m 9s
Documentation	1m 13s
Format	2m 36s
Build (ocaml-variants.5.3.0+trunk, ubuntu-latest, true)	4m 57s
Create local opam switch (macos-latest, 4.14)	7m 2s
Build (5.1.x, ubuntu-latest, true)	1m 45s
Create local opam switch (ubuntu-latest, 5)	5m 5s
Build monorepo benchmark docker image	4m 5s
Build (5.1.x, macos-latest, true)	2m 43s
Create local opam switch (ubuntu-latest, 4.14)	4m 54s
Nix (macos-latest)	1m 53s
Build (4.14.x, macos-13, true)	4m 25s
Nix (ubuntu-latest)	59s
Build (ocaml-base-compiler.4.14.2,system-msvc, windows-latest)	17m 6s
Build (ocaml-base-compiler.4.14.2,system-mingw, windows-latest)	9m 48s
Build (4.13.x, ubuntu-latest, true)	1m 38s
Build (4.08.x, ubuntu-latest, true)	1m 36s
Build (4.04.x, ubuntu-latest, true, true)	4m 54s
Build (4.02.x, ubuntu-latest, true)	4m 12s
	2h 15m 9s

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