Add support for CSES Problem URL

[Rishabh-malhotraa]

Requirement

Currently, Caucus only supports codeforces and atcoder links, but it would be great to add support for CSES links.
example https://cses.fi/problemset/task/1068

• Changes need to be made in the caucus server to add the functionality to scrape the CSES question from the get response.
  Also, some UI changes in the front-end, to tell the user that we support CSES links.

Files to be modified

• caucus-server/src/utils/scrapeQuestion.ts
• caucus/src/component/QuestionsPane/ProblemList/ProblemList.tsx

[Rishabh-malhotraa]

Similar to #43

[starkkumarkk1611]

@Rishabh-malhotraa Sir,
I have almost done both server-side and client-side
Just there is one Issue --
CSES problems contain some MathJax text. I need to add scripts to react but I tried and googled it and checked StackOverflow but I am not able to fix it please guide me - how to enable MathJax text to react., after fixing it I will make a pull request.
one more thing sir my most effort went for server-side, but there is no hacktoberfest tag sir, or any issue in the server repo, please add sir so It can also help me.

Thanks sir for giving me chance I would like to work on more Issue

[Rishabh-malhotraa]

Check this file out

The Math.Jax will be rendered automatically by Katex provided that the math expression is enclosed in the delimiter.

Example: $$\sum{a_i} = K$$ would be rendered as the following automatically, the delimiter here is $$

[starkkumarkk1611]

By mistake I removed the assignment.