PR #245: Address @samccann and @amsharma comments
    
    * Remove "Don't be shy" line from the instructions in posting a self-
      introduction.
    * Add a link to the `diversity-team` FAS group so people seeking a
      sponsor can see who is already a sponsored member of the DEI Team.
    
    Signed-off-by: Justin W. Flory (he/him) <jwf@redhat.com>