[Contracts] The contract generation process can be interrupted

[MarG66]

Preconditions:
The user must logged in on the "Lista contracte" tab.
At least one active volunteer and one template must be available.

Steps To Reproduce:

1. Click on the "Genereaza Contract" button
2. Complete all of the form steps using valid data
3. Click on "Trimite" button
4. After the contract generation modal is displayed click outside it

Expected Results:
4. No action is taken.

Actual Results:
4. The modal is closed and the contract generation process is interrupted, no contracts are generated.