Specify username and password if admin_interface_authentication is set to true in the sync gateway config

when admin_interface_authentication is set to true, not specifying a username and password will lead to missing pprof files, a 401 error being thrown and inconsistencies with admin API request logging. Please specify in the documentation that the username and password must be set in the sgcollect_info arguments to ensure logs and pprof files are properly collected

the flags are --sync-gateway-password and --sync-gateway-username

Reporter: Mohammed Madi
E-mail: mohammed.madi@couchbase.com