Very few tools out there allow you to enter your Mastodon account as part of your social media presence. If you are in a position to influence that, go for it.

Meanwhile, you may want to grab the Mastodon logo in svg format for use on websites and in print.

Grab it on Wikimedia: https://commons.wikimedia.org/wiki/File:Mastodon_Logotype_(Simple).svg

Remember, you can verify your profile links on Mastodon with a link back to your profile from the sites you link to.