Fix cram tests build-path-prefix-map substitutions #29823

Job	Run time
Coq 8.16.1	7m 5s
Documentation	53s
Build (macos-latest, 5.1.x)	13m 29s
Format	1m 2s
Build (ubuntu-latest, 5.1.x)	9m 0s
Nix (macos-latest)	2m 9s
Build (ocaml-variants.5.4.0+trunk, ubuntu-latest, true)	1m 35s
Build microbenchmarks	2m 37s
Nix (ubuntu-latest)	53s
Create local opam switch (macos-latest, 5)	5m 57s
Build (4.14.x, ubuntu-latest, true)	1m 31s
Create local opam switch (macos-latest, 4.14)	5m 25s
Build monorepo benchmark docker image	3m 24s
Wasm_of_ocaml	10m 10s
Create local opam switch (ubuntu-latest, 5)	5m 0s
Create local opam switch (ubuntu-latest, 4.14)	4m 39s
Build (4.14.x, macos-latest, true)	2m 9s
Build (5.1.x, macos-13, true)	4m 36s
Build (ocaml-base-compiler.4.14.2,system-msvc, windows-latest)	14m 41s
Build (ocaml-base-compiler.5.1.1,system-mingw, windows-latest)	8m 9s
Build (4.08.x, ubuntu-latest, true)	1m 25s
Build (4.04.x, ubuntu-latest, true, true)	4m 30s
Build (4.02.x, ubuntu-latest, true)	3m 49s
	1h 54m 8s

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