fix: Grammar in comment

Northstar.CustomServers/mod/scripts/vscripts/sh_progression.nut

@@ -89,7 +89,7 @@ bool function ClientCommand_SetProgression( entity player, array<string> args )
 /// Resets a specific Titan's Aegis rank back to `0`
 /// * `player` - The player entity to perform the action on
 /// * `args` - The arguments passed from the client command. `args[0]` should be a string corresponding to the chassis name of the Titan to reset.
-/// Valid chassis are: ion, tone, vanguard, northstar, ronin, legion and scorch.
+/// Valid chassis are: ion, tone, vanguard, northstar, ronin, legion, and scorch.
 ///
 /// Returns `true` on success and `false` on missing args.
 bool function ClientCommand_ResetTitanAegis( entity player, array<string> args )