refactor(gns3server,tests): StrEnum, ASYNC109 and others

gns3server/compute/virtualbox/__init__.py

@@ -85,7 +85,7 @@ class VirtualBox(BaseManager):
         self._vboxmanage_path = vboxmanage_path
         return vboxmanage_path
 
-    async def execute(self, subcommand, args, timeout=60):
+    async def execute(self, subcommand, args, timeout=60):  # noqa: ASYNC109 - operation-specific timeout is intentional
 
         # We use a lock prevent parallel execution due to strange errors
         # reported by a user and reproduced by us.