RESTServer : Failed to create socket

[Clovel]

Describe the bug
When launching the generator back-end, we can sometimes end prematurely with the following error log :

[ERROR] <RESTServer::open> Failed to create socket

This error occurs randomly. It seems it occurs more often hen launching the back-end several times successively.

To Reproduce
Steps to reproduce the behavior:

1. Checkout main branch
2. Build the project in ./build
3. Try to launch the generator back-end
4. See error

Expected behavior
Instead of the error log, we should get the following log :

[INFO ] Listening for request at: localhost:4000/OSCO-OD-Gen

Desktop (please complete the following information):

• OS: macOS Catalina 10.15.4 19E287 x86_64

Additional context
This is most likely a RESTServer issue. An issue was submitted at the RESTServer project : Clovel/RESTServer#1