tools: fix c++ code coverage on macOS
Recent libtool on macOS does not support the --coverage flag that was being passed through in the final linking stage. This change patches gyp-mac-tool to not pass the --coverage flag through to libtool. It is now possible to generate code coverage for src/ on macOS.
Fixes: https://github.com/nodejs/node/issues/19057
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
commit message follows commit guidelines