[release] update contributors list for 30.0

opam

@@ -45,6 +45,7 @@ authors: [
   "Alexander Kogtenkov"
   "Remi Lazarini"
   "Tristan Le Gall"
+  "Kilyan Le Gallic"
   "Jean-Christophe Léchenet"
   "Matthieu Lemerre"
   "Dara Ly"
@@ -67,6 +68,7 @@ authors: [
   "Virgile Robles"
   "Jan Rochel"
   "Muriel Roger"
+  "Cécile Ruet-Cros"
   "Julien Signoles"
   "Nicolas Stouls"
   "Kostyantyn Vorobyov"

src/plugins/gui/help_manager.ml

@@ -48,6 +48,7 @@ let show main_ui =
     "Alexander Kogtenkov";
     "Remi Lazarini";
     "Tristan Le Gall";
+    "Kilyan Le Gallic";
     "Jean-Christophe Léchenet";
     "Matthieu Lemerre";
     "Dara Ly";
@@ -70,6 +71,7 @@ let show main_ui =
     "Virgile Robles";
     "Jan Rochel";
     "Muriel Roger";
+    "Cécile Ruet-Cros";
     "Julien Signoles";
     "Nicolas Stouls";
     "Kostyantyn Vorobyov";