fix merge missing "fix index out of range when parsing output from

shell_scripts/get.sh"

capsulflask/spoke_model.py

@@ -84,6 +84,8 @@ class ShellScriptSpoke(VirtualizationInterface):
     self.validate_completed_process(completedProcess)
     lines = completedProcess.stdout.splitlines()
     ipaddr = lines[0].decode("utf-8")
+    if len(lines) == 0:
+      return None
 
     if not re.match(r"^([0-9]{1,3}\.){3}[0-9]{1,3}$", ipaddr):
       return None