chore: remove unnecessary condition

[is2ei]

This PR removes the unnecessary condition. Array.isArray() returns false for falsy values.

References

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray
• https://developer.mozilla.org/en-US/docs/Glossary/Falsy

Checklist

• [x] run npm run test and npm run benchmark
• [x] tests and/or benchmarks are included
• [ ] documentation is changed or added
• [ ] commit message and code follows the Developer's Certification of Origin and the Code of conduct