Mariabackup SST fails if "--log-bin" option is added with no value
to command line parameters at server startup. This is because the SST
scripts do not correctly interpret the "--- log-bin" option without a
value. This patch adds correct handling of the "--log-bin" parameter
without value to the general part of the parameter parsing (for SST
scripts) and fixes the problem. Also added a test that checks the
correct operation of the server after the fix.