It's probably possible to conditionally check if the directory where Homebrew
curses lives exists, but that feels a bit iffy for me, and also isn't very easy
to do in a Makefile. This solution is simpler, albeit a bit harder to find.
Once 'brew update' and 'brew upgrade' had been done, the qt@5
package did become available for installation and the original
line in the hints file worked, so put it back as it was.
move out-of-date hints files to the outdated folder.
rename the hints files, and hints/include files that are currently
named *.2020 to *.370 (next release number).