Attempt at fixing plotting errors on deployed app

[RemDelaporteMathurin]

I started noticing that on the deployed app, long simulations (eg. the ARC model) would run fine but then display:

Failed to run Pathsim simulation. Make sure the backend is running. : Failed to execute 'json' on 'Response': Unexpected end of JSON input

before plotting (and end up not plotting...)

This is an attempt at fixing that by adding more logic inside the infinite loop