fix lint, resolve code smell

Co-Authored-By: まっちゃとーにゅ <17376330+u1-liquid@users.noreply.github.com>

packages/backend/src/server/api/endpoints/admin/ad/list.ts

@@ -22,7 +22,7 @@ export const paramDef = {
 		limit: { type: 'integer', minimum: 1, maximum: 100, default: 10 },
 		sinceId: { type: 'string', format: 'misskey:id' },
 		untilId: { type: 'string', format: 'misskey:id' },
-		publishing: { type: 'boolean', default: null, nullable: true},
+		publishing: { type: 'boolean', default: null, nullable: true },
 	},
 	required: [],
 } as const;