feat: username inferring from discord nickname

src/core/options/addUsernameOption.ts

@@ -4,6 +4,5 @@ export default function addUsernameOption(option: SlashCommandStringOption) {
   return option
     .setName('username')
     .setDescription('The username you use in Blitz')
-    .setAutocomplete(true)
-    .setRequired(true);
+    .setAutocomplete(true);
 }