L3 conntrack helper: Use singular name consistently

We use singular form for delete command argument in all places.
This commit replaces conntrack-helper-ids with a singular form.
The only visible change is a fix for the help message below.

  openstack network l3 conntrack helper delete
      <router>
      <conntrack-helper-ids>
      [<conntrack-helper-ids> ...]

Change-Id: I50bbd9f6199071bb86cbb2f37c45ebda1de58433

Author: amotoki

openstackclient/network/v2/l3_conntrack_helper.py

@@ -99,8 +99,8 @@ def get_parser(self, prog_name):
             help=_('Router that the conntrack helper belong to')
         )
         parser.add_argument(
-            'conntrack_helper_ids',
-            metavar='<conntrack-helper-ids>',
+            'conntrack_helper_id',
+            metavar='<conntrack-helper-id>',
             nargs='+',
             help=_('The ID of the conntrack helper(s) to delete')
         )
@@ -112,7 +112,7 @@ def take_action(self, parsed_args):
         result = 0
 
         router = client.find_router(parsed_args.router, ignore_missing=False)
-        for ct_helper in parsed_args.conntrack_helper_ids:
+        for ct_helper in parsed_args.conntrack_helper_id:
             try:
                 client.delete_conntrack_helper(
                     ct_helper, router.id, ignore_missing=False)
@@ -123,7 +123,7 @@ def take_action(self, parsed_args):
                           {'ct_helper': ct_helper, 'e': e})
 
         if result > 0:
-            total = len(parsed_args.conntrack_helper_ids)
+            total = len(parsed_args.conntrack_helper_id)
             msg = (_("%(result)s of %(total)s L3 conntrack helpers failed "
                    "to delete.") % {'result': result, 'total': total})
             raise exceptions.CommandError(msg)

openstackclient/tests/unit/network/v2/test_l3_conntrack_helper.py

@@ -127,7 +127,7 @@ def test_delete(self):
             self.ct_helper.id
         ]
         verifylist = [
-            ('conntrack_helper_ids', [self.ct_helper.id]),
+            ('conntrack_helper_id', [self.ct_helper.id]),
             ('router', self.ct_helper.router_id),
         ]
         parsed_args = self.check_parser(self.cmd, arglist, verifylist)
@@ -143,7 +143,7 @@ def test_delete_error(self):
             self.ct_helper.id
         ]
         verifylist = [
-            ('conntrack_helper_ids', [self.ct_helper.id]),
+            ('conntrack_helper_id', [self.ct_helper.id]),
             ('router', self.router.id),
         ]
         self.network.delete_conntrack_helper.side_effect = Exception(