remove padding from sidebar stacks
remove padding from sidebar stacks

jupyter/jupyter-js-plugins,blink1073/jupyter-js-plugins,blink1073/jupyter-js-plugins,jupyter/jupyter-js-plugins,blink1073/jupyter-js-plugins,blink1073/jupyter-js-plugins,jupyter/jupyter-js-plugins,jupyter/jupyter-js-plugins,jupyter/jupyter-js-plugins,blink1073/jupyter-js-plugins