If "make check" is run before "make install" I get "error running
'/usr/local/Cellar/gnupg21/2.1.19/bin/gpg2': probably not installed"
This seems specifically to affect gpgconf.scm and tofu.scm.
The path /usr/local/Cellar/gnupg21/2.1.19/bin/gpg2 is indeed where gpg2 gets
installed after "make install", but that's not where it is if we run "make
check" before "make install", since it hasn't been installed in the prefix yet.
This did not occur with 2.1.18.
Here is a full log: