”ArgumentNullException: Array cannot be null” error is printed when passing an empty string to fileName of WWWForm.AddBinaryData and then access the data property

How to reproduce:
1. Open the user’s attached “WWWFormError.zip” project
2. Enter Play Mode
3. Observe the Console window

Expected result: “System.Byte[]” is printed
Actual result: “ArgumentNullException: Array cannot be null” error is printed

Reproducible with: 2021.1.0a1, 2021.1.28f1, 2021.3.22f1, 2022.2.15f1, 2023.1.0b12, 2023.2.0a10
Not reproducible with: 2020.3.47f1, 2020.2.0b3

Reproduced on: macOS 13.2.1 (Intel)