Fix typo: Addtional -> Additional

Signed-off-by: Rui Cao <ruicao@alauda.io>

docker/api/container.py

@@ -465,7 +465,7 @@ class ContainerApiMixin(object):
             dns_opt (:py:class:`list`): Additional options to be added to the
                 container's ``resolv.conf`` file
             dns_search (:py:class:`list`): DNS search domains.
-            extra_hosts (dict): Addtional hostnames to resolve inside the
+            extra_hosts (dict): Additional hostnames to resolve inside the
                 container, as a mapping of hostname to IP address.
             group_add (:py:class:`list`): List of additional group names and/or
                 IDs that the container process will run as.

docker/models/containers.py

@@ -558,7 +558,7 @@ class ContainerCollection(Collection):
             environment (dict or list): Environment variables to set inside
                 the container, as a dictionary or a list of strings in the
                 format ``["SOMEVARIABLE=xxx"]``.
-            extra_hosts (dict): Addtional hostnames to resolve inside the
+            extra_hosts (dict): Additional hostnames to resolve inside the
                 container, as a mapping of hostname to IP address.
             group_add (:py:class:`list`): List of additional group names and/or
                 IDs that the container process will run as.