Replace deprecated inspect.getargspec call

Replace inspect.getargspec with inspect.getfullargspec in the cloud
utils.

Change-Id: Iac99f7cc69c2e1e6ff6f186c4360d51e92d3a781
(cherry picked from commit 7cee92d5e3)

openstack/cloud/_utils.py

@@ -362,7 +362,7 @@ def valid_kwargs(*valid_args):
     #
     @decorator
     def func_wrapper(func, *args, **kwargs):
-        argspec = inspect.getargspec(func)
+        argspec = inspect.getfullargspec(func)
         for k in kwargs:
             if k not in argspec.args[1:] and k not in valid_args:
                 raise TypeError(