🐛(backend) submit for signature handle timeout and exception on delete signing procedure

[jonathanreveille]

Purpose

When the method submit_for_signature needs to delete a signing procedure because some elements have changed overtime in the contract definition and before the student signed the document, it appears that it may take a while on the signature provider side to execute the deletion.

In order to handle and update our contract, we have added a try except block to catch the timeout issue, and proceed to update the contract as if we would have received the response from the signature provider.

Before we added the fix, the contract would keep the outdated references that would not work when the student wanted to sign the document, causing another error because it has already been deleted after the timeout we have set in the signature backend on the signature provider's side. Now, when get a NOT_FOUND status code on the response when attempting to delete the outdated reference at the signature provider. We now make sure that handle this case and reset the contrat for the next submission.

Proposal

• [x] Add try except block in submit_for_signature to handle BackendTimeout and NOT_FOUND status code