update authors

Author: feross

AUTHORS.md

@@ -68,5 +68,6 @@
 - mathmakgakpak (44949126+mathmakgakpak@users.noreply.github.com)
 - jkkang (jkkang@smartauth.kr)
 - Deklan Webster (deklanw@gmail.com)
+- Martin Heidegger (martin.heidegger@gmail.com)
 
 #### Generated by bin/update-authors.sh.