Add community links (GitHub, slack, etc.) to website footer

[Adityakumar37]

Description:

Currently, the footer section of the [FOSSology website] does not include any links to the project’s GitHub repository, community channels, or contribution pages.

Because of this, it can be difficult for new visitors and potential contributors to quickly locate where the community is active or how to get involved. Adding these links in the footer will make the site more accessible, welcoming, and contributor-friendly.