Fix Windows Bug for Retrieving Problems

[leonardo-delfino]

The intention of this PR is to fix the current bug that makes the command cpb clone only retrieve the first problem when using it on WSL. The problem derives from the fact that the extension Competitive Companion has a huge delay when parsing the problems on Windows. To fix this, instead of just parsing everything, the total number of problems is parsed and the code waits to get each of the problem of the cloned contest. This assures to retrieve each problem correctly, not caring for the delay (it is a huge delay and it varies). I have tested the code using Chrome on Windows and both Chrome and Firefox (latest version for both browsers) on Linux (Ubuntu). Firefox on Windows still has to be tested.

[searleser97]

I think we are not handling the case when different batches are being sent at the same time, we could use the batch id to fix that.

[leonardo-delfino]

I think we are not handling the case when different batches are being sent at the same time, we could use the batch id to fix that.

Ok. I will work on these changes next week.