Delete magento.py
Delete magento.py

From https://github.com/gwillem/magento-malware-scanner : ```The opensource malware scanner is no longer maintained as of 2018...```

So, I bring the last ```/gwillem/magento-malware-scanner``` snapshot to ```static/malicious/magentocore.txt``` (https://github.com/stamparm/maltrail/pull/6930/commits/06ddc09195ee6b2dcb383073491743536dfd3fb1) and put the PR for ```/feeds/magento.py``` to be deleted.
stamparm/maltrail,stamparm/maltrail,stamparm/maltrail,stamparm/maltrail