fix(ApplicationCommandManager): allow passing 0n to defaultMemberPermissions (v13)

#8312 v13.9.1

src/managers/ApplicationCommandManager.js

@@ -235,7 +235,8 @@ class ApplicationCommandManager extends CachedManager {
     }
 
     if ('defaultMemberPermissions' in command) {
-      default_member_permissions = command.defaultMemberPermissions
+      default_member_permissions =
+        command.defaultMemberPermissions !== null
           ? new Permissions(command.defaultMemberPermissions).bitfield.toString()
           : command.defaultMemberPermissions;
     }

src/structures/ApplicationCommand.js

@@ -389,9 +389,8 @@ class ApplicationCommand extends Base {
     }
 
     if ('defaultMemberPermissions' in command) {
-      defaultMemberPermissions = command.defaultMemberPermissions
-        ? new Permissions(command.defaultMemberPermissions).bitfield
-        : null;
+      defaultMemberPermissions =
+        command.defaultMemberPermissions !== null ? new Permissions(command.defaultMemberPermissions).bitfield : null;
     }
     // Check top level parameters
     const commandType = typeof command.type === 'string' ? command.type : ApplicationCommandTypes[command.type];