Fix edit_config multiline commands on IOS (ansible#35375)

* Fix edit_config multiline commands on IOS

The current code for multiline commands in IOS is broken: If you
pass a dict containing a command, prompt and answer it is seen
later as unicode string, but if you do a json.loads it fails
as the keys/values are enclosed in single quotes but JSON requires
double quotes.

Fixes ansible#23539

* Fix pep8

* Use ast literal_eval

It's safe to use, as it is just for types and wont execute arbitrary code.

lib/ansible/plugins/cliconf/ios.py

@@ -19,6 +19,7 @@
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
+import ast
 import re
 import json
 
@@ -71,7 +72,7 @@ def get_config(self, source='running', flags=None):
     def edit_config(self, command):
         for cmd in chain(['configure terminal'], to_list(command), ['end']):
             try:
-                cmd = json.loads(cmd)
+                cmd = ast.literal_eval(cmd)
                 command = cmd['command']
                 prompt = cmd['prompt']
                 answer = cmd['answer']