Add tests for filebrowser buttons
Add tests for filebrowser buttons

charnpreetsingh185/jupyterlab,charnpreetsingh185/jupyterlab,jupyter/jupyterlab,jupyter/jupyterlab,jupyter/jupyterlab,eskirk/jupyterlab,eskirk/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,charnpreetsingh185/jupyterlab,eskirk/jupyterlab,charnpreetsingh185/jupyterlab,jupyter/jupyterlab,charnpreetsingh185/jupyterlab,eskirk/jupyterlab