remove empty runinfo in the existing_interfaces.tex
remove empty runinfo in the existing_interfaces.tex

idaholab/raven,idaholab/raven,idaholab/raven,joshua-cogliati-inl/raven,idaholab/raven,joshua-cogliati-inl/raven,joshua-cogliati-inl/raven,idaholab/raven,idaholab/raven,idaholab/raven,joshua-cogliati-inl/raven,joshua-cogliati-inl/raven,joshua-cogliati-inl/raven,joshua-cogliati-inl/raven