perf: simplify registerService return on failure

Simplified the return statement structure of the registerService function. Removed an unnecessary else clause and returned failure directly instead for better readability and cleaner code structure.

src/services/authentication/register.service.ts

@@ -44,12 +44,11 @@ async function registerService(data: IRegisterInput): Promise<IRegisterOutput> {
 			id: User.id,
 			token: token,
 		};
-	} else {
-		return {
-			success: false,
-			message: "Failed to register user",
-		};
 	}
+	return {
+		success: false,
+		message: "Failed to register user",
+	};
 }
 
 export default registerService;