[tests] Try several times to connect the ssh server
[tests] Try several times to connect the ssh server

Sometimes, as the OCI container is run in detached mode, it is possible
the actual server is not ready yet to handle SSH traffic. The goal of
this PR is to try several times (max 3). The mechanism is the same as
for the connection to the docker machine.

libssh2/libssh2,libssh2/libssh2,libssh2/libssh2,libssh2/libssh2