Update socials

Author: krassowski

about.html

@@ -440,7 +440,8 @@
   - name: Michał Krassowski
     affiliation: Quansight
     photo: Michal_Krassowski.jpg
-    twitter_handle: krassowski_m
+    mastodon: https://fosstodon.org/@krassowski
+    bluesky_handle: @krassowski.bsky.social
     gh_handle: krassowski
     linkedin: https://www.linkedin.com/in/michal-krassowski/
     subproject: Jupyter Frontends