Migrate static assets to a new repo for centralized management

[nishant-nayak]

Moving static assets like Society logos, Branch logos and other images ensures consistency across all website repositories (blog, gyan and virtual-expo).

Tasks

• Identify common assets across all 4 website repositories
• Move the assets to a new repository
• Update the asset links on all 4 repositories to fetch assets from the new repository

[nishant-nayak]

Common assets repository: https://github.com/IEEE-NITK/website-assets