fix: Update social icon on about page

[mcanouil]

This pull request updates the social icon on the about page. The commit fixes issue #165 by making the following changes:

• In the _quarto.yml file, the Twitter social icon link is updated to point to https://x.com/MickaelCanouil.

• In the coeos.scss file, the flex-wrap property is added to the about-links class to ensure proper wrapping of social icons.

• In the index.qmd file, the Twitter social icon link is updated to point to https://x.com/MickaelCanouil and the aria-label attribute is updated accordingly.

Fixes #165