Disable tests for CentOS 6
Disable tests for CentOS 6

CentOS 6 doesn't have proper version of python-gevent

rtsisyk/tarantool,mejedi/tarantool,rtsisyk/tarantool,mejedi/tarantool,ocelot-inc/tarantool,rtsisyk/tarantool,ocelot-inc/tarantool,mejedi/tarantool,mejedi/tarantool,ocelot-inc/tarantool,ocelot-inc/tarantool,rtsisyk/tarantool