Timeout for big requests

[esyriani]

Describe the bug When issuing a long request, like the ones below, we sometimes get a timeout error:

• Importing thousands of papers
• Assigning all papers
• Creating a project
• Displaying the chart results of the classification

We are then blocked from accessing ReLiS.

The error is: 504 Gateway Time-out The server didn't respond in time.

[esyriani]

A workaround is to access ReLiS in a different browser or in Private/Incognito mode