Delete test.yml

This workflow was used to investigate #164

- It seems like binaries built with MinGW on Ubuntu 20.04 are being detected as a Trojan by BitDefender and other vendors: https://www.virustotal.com/gui/file/420587335d94788b376751745d32d1003663e88c4383c433e5ea920a6f2308f8
- I couldn't reproduce on Ubuntu 22.04 (save for one vendor): https://www.virustotal.com/gui/file/0e31b49d38e10f769915f48a6c1f66c9006453e5bf4f1fff37de227a80577721
- Binaries built with mingw-w64-gcc 12.2.0 on my machine are not flagged as malicious

So, unless Ubuntu is distributing compromised packages, I'm pretty sure this is a false positive. I've never seen anything suspicious in DPF's code.

Also, I couldn't find any info regarding the threat that these vendors call `Trojan.Ceram.Gen.1`. I don't know what it is supposed to do.