Ensure all GNU coreutils are available

macOS Ventura (14) has added a realpath utility which causes brew's
coreutils package to install realpath as grealpath. Follow brew's
configuration advice for the PATH variable.

Author: dra27

.github/scripts/main/preamble.sh

@@ -10,6 +10,9 @@ fi
 echo "Cache -> $CACHE"
 OCAML_LOCAL=$CACHE/ocaml-local
 OPAM_LOCAL=$CACHE/opam-local
+if [ "$RUNNER_OS" = 'macOS' ]; then
+  PATH="/opt/homebrew/opt/coreutils/libexec/gnubin:$PATH"
+fi
 PATH=$OPAM_LOCAL/bin:$OCAML_LOCAL/bin:$PATH; export PATH
 
 OPAM_COLD=${OPAM_COLD:-0}

master_changes.md

@@ -70,6 +70,7 @@ users)
 ## Build
 
 ## Infrastructure
+  * Ensure GNU coreutils available on the macOS 14 CI runners [#5938 @dra27]
 
 ## Release scripts