install ocaml in dockerfile instead of postCreate.sh (#8230) #9469

Job	Run time
test-devcontainer	16m 57s
build-compiler (macos-15-intel, 5.3.0, true, darwin-x64, x86_64-apple-darwin)	9m 52s
build-compiler (ubuntu-24.04, ocaml-variants.5.0.0+options,ocaml-option-static, linux-x64, x86_64...	4m 53s
build-compiler (windows-2025, 5.3.0, true, win32-x64, x86_64-pc-windows-gnu, .exe)	10m 15s
build-compiler (ubuntu-24.04, ocaml-variants.5.3.0+options,ocaml-option-static, true, true, linux...	4m 56s
build-compiler (ubuntu-24.04-arm, ocaml-variants.5.3.0+options,ocaml-option-static, true, true, t...	5m 43s
build-compiler (macos-15, 5.3.0, true, darwin-arm64, aarch64-apple-darwin)	7m 33s
api-docs	14s
pkg-pr-new	54s
test-integration-rewatch (ubuntu-24.04)	3m 34s
test-integration-rewatch (windows-2025)	7m 25s
test-installation-npm (macos-15-intel)	28s
test-installation-npm (windows-2025)	48s
test-installation-pnpm (ubuntu-24.04-arm)	18s
test-installation-npm (ubuntu-24.04)	13s
test-installation-npm (ubuntu-24.04-arm)	17s
test-installation-pnpm (macos-15-intel)	30s
test-installation-npm (macos-15)	26s
test-integration-rewatch (ubuntu-24.04-arm)	2m 51s
test-installation-pnpm (ubuntu-24.04)	12s
test-integration-rewatch (macos-15-intel)	6m 18s
test-installation-pnpm (windows-2025)	41s
test-integration-rewatch (macos-15)	5m 2s
test-installation-pnpm (macos-15)	18s
publish	0s
	1h 30m 38s

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