Panic while unwrap a None value

I did fuzz runs on the `parse` target and the fuzzer detected a panic: ``` thread 'main' panicked at /repro/latest/pdf/pdf/src/object/function.rs:140:96: called `Option::unwrap()` on a `None` value ``` I attached an input the fuzzer generated that caused the related panic: [4d605a3c68717cdf2bbbe69060664453f2b5bc0ec5e92edd12f41deec171bfc7.zip](https://github.com/user-attachments/files/19976249/4d605a3c68717cdf2bbbe69060664453f2b5bc0ec5e92edd12f41deec171bfc7.zip)