Mac Error: CFError -25293

I want to use smimesign on my Mac for git. I'm a happy windows user of this already.

In Mac 15.3.1 (24D70) I did everything needed to sign commits and I got

```bash
$ git commit -S -m "tt" README.md
error: gpg failed to sign the data
fatal: failed to write commit object
```

So I tried around and found out:

```
$ echo "Test" > test.txt
$ smimesign -su 'Maxxxx xxxxxxdt ' test.txt
failed to sign message: CFError -25293
```