Add hacathons

[vedpawar2254]

Summary of your changes

Description

Added a comprehensive list of popular hackathons and coding competitions, including major events like HackMIT, NASA Space Apps Challenge, Google CodeJam, and others. This addition provides users with various options to explore, participate in, and learn about different hackathon events and competitions.

Fixes #1964

Checklist

• [x] My change follows the Contributing Guidelines
• [x] I have added only one new link to the list.
• [x] I have checked that the link that I added does NOT exist in the project already.
• [x] I have sorted the link alphabetically under the related section.

[vedpawar2254]

please consider this for hactober2024