Add support for BAPS OJ

[touhidurrr]

resolves #385

[jmerle]

Thank you! I can't test it because I have no BAPS OJ account and there's no public registration page, but I don't see any problems in this PR. Will be released soon.

[touhidurrr]

I can't test it because I have no BAPS OJ account and there's no public registration page

Yes, BAPS OJ is a private judge that was made to run ICPC Dhaka Regional 2023 (and possibly future ICPC Dhaka Regional Contests) replacing CodeMarshal (although no official announcement about it was made about it but i kind of guessed it since they have taken CM down for now). The judge offers no registration page as username / password is made for participating teams by the OJ maintainers emailed before the contest for contests like this. Since I was also a participant this time, I could test it and made a PR.

Although I cannot share my team credentials in public, since the API is weirdly open for the judge you should be able to test it by making API requests.

Fun fact is the issue was actually made some time before the preliminary contest began and i responded to it because i was bored as the contest was delayed. I also wrote some test code that worked (again a little while before the contest) but didn’t upload it because it did not look stable. Later implemented the API to make a PR.