Update index.md (rms-open-letter#18)

Added Rosanna, Steven, Lars, and Christopher.

Co-authored-by: Elana Hashman <[email protected]>

Author: Molly de Blanc

index.md

@@ -49,6 +49,10 @@ Signed,
 - David Thompson (GNU Guile/Guix contributor, ex-FSF)
 - Jesse Cooke
 - Andrej Shadura
+- Rosanna Yuen (GNOME Foundation)
+- Steven DuBois
+- Lars Wirzenius
+- Christopher Schmidt
 - Amy Troschinetz
 - Antoine Beaupré AKA anarcat (Debian Developer, former FSF member)
 - Emmanuele Bassi (GNOME Foundation)