chg: [threat-actor] Iron Group added

ref: https://www.intezer.com/iron-cybercrime-group-under-the-scope-2/

clusters/threat-actor.json

@@ -5719,7 +5719,18 @@
         ]
       },
       "uuid": "dc3edacc-bb24-11e8-81fb-8c16458922a7"
+    },
+    {
+      "value": "Iron Group",
+      "description": "Iron group has developed multiple types of malware (backdoors, crypto-miners, and ransomware) for Windows, Linux and Android platforms. They have used their malware to successfully infect, at least, a few thousand victims.",
+      "meta": {
+        "refs": [
+          "https://www.intezer.com/iron-cybercrime-group-under-the-scope-2/"
+        ],
+        "synonyms": "Iron Cyber Group"
+      },
+      "uuid": "6a0ea861-229a-45a6-98f5-228f69b43905"
     }
   ],
-  "version": 57
+  "version": 59
 }