[BUG]: Re-positioning of the GitHub icon with the rest icons.

[Hammad-Raza-Khan]

Issue description
The GitHub icon is placed separately at the bottom right of the website; whereas the rest of the social icons are on the left.
Therefore, it would be more professional if it was placed with the rest of them.

Steps to reproduce the issue

1. Go to 'grpc.io'
2. Click on 'scroll'
3. Scroll down to bottom/end.
4. GitHub icon is placed at right.

Expected behavior
It would be more professional if the GitHub icon was placed with the rest of them on the left part of the screen.

Screenshots

[eugeneo]

@thisisnotapril

[sergiitk]

cc @temawi

[YifeiZhuang]

cc. @thisisnotapril