The Azure Pipelines MacOS vmImage has an old version of OpenSSL (1.0.2t)
installed at /usr/local/opt/openssl. Normally with Homebrew this directory
would be linked to the currenly installed version of OpenSSL (1.1.x) in
/usr/local/Cellar, but since it has been installed manually here it interferes
with linking libssl.a and libcrypto.a static libraries which causes the build
to fail.
Chris Simons
Nelson Chen