Fixing "sshd role README.md examples use incorrect role name"
    
    This pr fixes 2 issues.
    1) Replacing
        - role: willshersystems.sshd
       with
        - role: fedora.linux_system_roles.sshd
    2) Avoiding unnecessary conversion. E.g.,
         https://travis-ci.org/willshersystems/ansible-sshd.svg
       was accidentally converted to:
         https://travis-ci.org/willshersystems/fedora.linux_system_roles.sshd.svg
    
    Related: rhbz#1961404