ci: Make getopt path architecture agnostic

Author: hebasto

ci/test/04_install.sh

@@ -78,7 +78,7 @@ if [ -n "$PIP_PACKAGES" ]; then
   if [ "$CI_OS_NAME" == "macos" ]; then
     sudo -H pip3 install --upgrade pip
     # shellcheck disable=SC2086
-    IN_GETOPT_BIN="/usr/local/opt/gnu-getopt/bin/getopt" ${CI_RETRY_EXE} pip3 install --user $PIP_PACKAGES
+    IN_GETOPT_BIN="$(brew --prefix gnu-getopt)/bin/getopt" ${CI_RETRY_EXE} pip3 install --user $PIP_PACKAGES
   else
     # shellcheck disable=SC2086
     ${CI_RETRY_EXE} CI_EXEC pip3 install --user $PIP_PACKAGES