make refresh-sample-testdata does not refresh non-diff files on macOS

[egibs]

When running make refresh-sample-testdata for #502, I noticed that the script would stop after the diffs are processes, which is here:

for f in $(find "${test_data}" -name "*.simple"); do
	prog=$(echo $f | sed -e s#"${test_data}/"## -e s#\.simple\$##)
	if [[ -f "${prog}" ]]; then
		addq ${malcontent} --format=simple -o "${f}" analyze "${prog}"
	fi
done

As far as I can tell, we get to the [[ -f "${prog}" ]] test and it fails for whatever reason. Could be that something is wrong with my local repository but I also made a fresh clone of it today.

[egibs]

Updated the title. The script runs without issue on Linux.