fix: stabilize tests with synchronous DB init and handle Bandit security findings

decnet/network.py

@@ -9,7 +9,7 @@ Handles:
 """
 
 import os
-import subprocess
+import subprocess  # nosec B404
 from ipaddress import IPv4Address, IPv4Interface, IPv4Network
 
 import docker
@@ -24,7 +24,7 @@ HOST_IPVLAN_IFACE = "decnet_ipvlan0"
 # ---------------------------------------------------------------------------
 
 def _run(cmd: list[str], check: bool = True) -> subprocess.CompletedProcess:
-    return subprocess.run(cmd, capture_output=True, text=True, check=check)
+    return subprocess.run(cmd, capture_output=True, text=True, check=check)  # nosec B603 B404
 
 
 def detect_interface() -> str: