Various fixes

[NicoPennec]

Problem

• Exporting the asset list may sometimes fail.
• The task list of Edits displays an empty Sequence column, but an Edit is not linked to Sequence.
• The form to create or edit a Custom Action allows an empty name, but the server failed without this field.
• Some npm dependencies are outdated.

Solution

• Fix CSV export of the asset list when it includes shared assets.
• Hide the sequence column for Edit tasks.
• Fix required fields on the Custom Action form.
• Bump npm dependencies.