Add post-rebase missing files
    
    During rebase rpminspect.yaml and README.rst files were removed as they
    are not part of the build.
    
    Re-adding these files. In addition, add spec marker for source-git handling.
    
    Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
    
    Resolves: #bz#1997408