added atcoder contest page

[agastya3636]

Description

Created a get_contests() function which scrap the contest page and return in json format.

Resolves: #974

Checklist

Before submitting this pull request, kindly verify that the ensuing checkpoints have been reached.

• Have you adhered to the repository's defined coding convention rules?
• Have you updated the 'documentation.md' file with the method/function documentation?
• Have you sent a message along with the result or response?
• Have you used the try-catch technique?
• Has the method/class been added to the documentation (md file)?

Screenshots

Uploading a screenshot illustrating the approach you developed for validation is required.

Additional Notes/Comments

Any additional remarks or suggestions concerning this pull request are welcome.

---

I certify that I have carried out the relevant checks and provided the requisite screenshot for validation by submitting this pull request.
I appreciate your contribution.

[nikhil25803]

Great work @agastya3636 !!
Do not forget to

• Share your contribution on socials and tag Clueless 🫂
• Give this repository a star ✨
• Follow Clueless Community on GitHub ✅