Add: Allow to create gvm Enums from all kind of objects

gvm/_enum.py

@@ -4,7 +4,7 @@
 #
 
 from enum import Enum as PythonEnum
-from typing import Optional
+from typing import Any, Optional
 
 from typing_extensions import Self
 
@@ -16,6 +16,10 @@ class Enum(PythonEnum):
     Base class for Enums in python-gvm
     """
 
+    @classmethod
+    def _missing_(cls, value: Any) -> Optional[Self]:
+        return cls.from_string(str(value) if value else None)
+
     @classmethod
     def from_string(
         cls,