pkg: build and make ocamlformat dev-tool available #28079

Job	Run time
Coq 8.16.1	5m 45s
Coverage (4.14.x)	5m 45s
Build microbenchmarks	5m 10s
Build (macos-latest, 4.14.x)	5m 48s
Build (ubuntu-latest, 4.14.x)	5m 45s
Create local opam switch (macos-latest, 5)	5m 38s
Documentation	1m 14s
Format	2m 38s
Build (ocaml-variants.5.3.0+trunk, ubuntu-latest, true)	4m 59s
Create local opam switch (macos-latest, 4.14)	5m 47s
Build (5.1.x, ubuntu-latest, true)	1m 43s
Create local opam switch (ubuntu-latest, 5)	5m 6s
Build monorepo benchmark docker image	3m 56s
Create local opam switch (ubuntu-latest, 4.14)	5m 31s
Build (5.1.x, macos-latest, true)	2m 34s
Nix (macos-latest)	2m 20s
Build (4.14.x, macos-13, true)	5m 50s
Nix (ubuntu-latest)	58s
Build (ocaml-base-compiler.4.14.2,system-msvc, windows-latest)	5m 41s
Build (ocaml-base-compiler.4.14.2,system-mingw, windows-latest)	5m 34s
Build (4.13.x, ubuntu-latest, true)	1m 40s
Build (4.08.x, ubuntu-latest, true)	1m 42s
Build (4.04.x, ubuntu-latest, true, true)	4m 48s
Build (4.02.x, ubuntu-latest, true)	4m 9s
	1h 40m 1s

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