ci, macos: Use --break-system-packages with Homebrew's python

Homebrew's [email protected] is marked as externally managed (PEP 668),
necessitating different approaches for installing Python packages.

For more details, please refer to https://github.com/orgs/Homebrew/discussions/3404.

Author: hebasto

ci/test/00_setup_env_mac_native.sh

@@ -7,7 +7,9 @@
 export LC_ALL=C.UTF-8
 
 export HOST=x86_64-apple-darwin
-export PIP_PACKAGES="zmq"
+# Homebrew's [email protected] is marked as externally managed (PEP 668).
+# Therefore, `--break-system-packages` is needed.
+export PIP_PACKAGES="--break-system-packages zmq"
 export GOAL="install"
 export BITCOIN_CONFIG="--with-gui --with-miniupnpc --with-natpmp --enable-reduce-exports"
 export CI_OS_NAME="macos"