Update apt_gamaredon.txt
Update apt_gamaredon.txt

https://twitter.com/h2jazi/status/1371445133560983552
https://www.virustotal.com/gui/file/e7f61cd965886e1ca75d5bd3d3140ce7c78c78c245d57c285af83711148b7472/detection

+ minor refactoring for doc-trails.
stamparm/maltrail,stamparm/maltrail,stamparm/maltrail,stamparm/maltrail