Dune 3.8.1

We've just released a patch version of Dune to fix regressions introduced in Dune 3.8.0.

In particular, we've reverted some cross-compilation improvements that caused build failures when using ppx_runtime_libraries and we'll revisit them in a future version of Dune.

See full changelog

• Fix a crash when using a version of Coq < 8.13 due to the native compiler config variable being missing. We now explicitly default to (mode vo) for these older versions of Coq. (dune#7847, fixes dune#7846, @Alizter)
• Duplicate installed Coq theories are now allowed with the first appearing in COQPATH being preferred. This is inline with Coq's loadpath semantics. This fixes an issue with install layouts based on COQPATH such as those found in nixpkgs. (dune#7790, @Alizter)
• Revert dune#7415 and dune#7450 (Resolve ppx_runtime_libraries in the target context when cross compiling) (dune#7887, fixes dune#7875, @emillon)