Draft: Student dashboard: open assignment with a link rather than a call to ipylab
The student dashboard includes buttons to open the assignments. Up to now the opening itself was done by calling the JupyterLab interface through ipylab. After this change, the button is replaced by a simple html link, styled as a button.
Advantages:
- The student dashboard does not depend on ipylab anymore.
- This is a step toward removing a little used dependency.
- It's also a step toward integration in dashboard (like voila) that sometimes blocks the interaction with the surrounding jupyterlab.
- The user can check in advance in the browser which file will be open upon clicking.
Caveat: plain html links are not yet supported by jupyterlab-myst 2.4.2. See https://github.com/jupyter-book/jupyterlab-myst/issues/64.
Other changes:
- The action is made active as soon as the assignment's work dir exists, even if the student is not yet authentified.
- The action is deactivated if there is no index or README file in the work dir to point to.