Propagate ssh-agent authentication socket (#9926)
Propagate ssh-agent authentication socket (#9926)

In case that SSH_AUTH_SOCK is defined, two items will be added to the
docker run command:
1) A propageted ssh authentication socket value , to support
   an underlying ssh calls inside the running contianer.
2) A mounted volume for ssh channel.

Co-authored-by: Samuel Panijel <8c9ed37cbd994028bc20abb258d5c0798d4a660c@arm.com>
dmlc/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm