Do not SKIP_BUILD_RPATH to let libmysql_api_test run during the build.
There is no WITH_UNITTEST, but there is WITH_UNIT_TESTS.
Do not install and immediately delete mysql-test.
There is no "basedir=" in mysql_install_db.
Uses the HTTPS url for cases where the existing URL has a permanent
redirect. For each domain, at least one fixed derivation URL was
downloaded to test the domain is properly serving downloads.
Also fixes jbake source URL, which was broken.
At least PHP expects a libmysqlclient_r which was the thread-safe
variant of libmysqlclient, but has been dropped since this is
guaranteed for libmysqlclient now.