Fix a docstring typo in manager.py

TrivialFix

Change-Id: Ifd276aa237f6e5db9a77dc172a898f4958f647a7
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index ab388c2..cd3501e 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -789,7 +789,7 @@
 
     def _get_server_port_id_and_ip4(self, server, ip_addr=None):
         ports = self._list_ports(device_id=server['id'], fixed_ip=ip_addr)
-        # A port can have more then one IP address in some cases.
+        # A port can have more than one IP address in some cases.
         # If the network is dual-stack (IPv4 + IPv6), this port is associated
         # with 2 subnets
         p_status = ['ACTIVE']