fix alt tag in readme

README.md

@@ -23,7 +23,7 @@ Please [visit the website](https://crafatar.com) for details.
 
 ## Contact
 
-* You can follow us on [![t](https://favicons.githubusercontent.com/twitter.com)@crafatar](https://twitter.com/crafatar)
+* You can follow us on [![twitter ](https://favicons.githubusercontent.com/twitter.com)@crafatar](https://twitter.com/crafatar)
 * Open an [issue](https://github.com/crafatar/crafatar/issues/) on GitHub
 * You can [join us](https://webchat.esper.net/?channels=crafatar) in #crafatar on irc.esper.net.