HA network tenants are not deleted

Issue

• HA network tenants are not deleted:
• Reproducer steps:

1. create new tenant
2. create router
3. delete router

[stack@instack ~]$ neutron router-list
+--------------------------------------+----------+-----------------------+-------------+------+
| id                                   | name     | external_gateway_info | distributed | ha   |
+--------------------------------------+----------+-----------------------+-------------+------+
| 09d5114d-5c8e-48d2-bca7-01ad10304d62 | router-1 | null                  | False       | True |
+--------------------------------------+----------+-----------------------+-------------+------+

$ neutron net-list
+--------------------------------------+----------------------------------------------------+-------------------------------------------------------+
| id                                   | name                                               | subnets                                               |
+--------------------------------------+----------------------------------------------------+-------------------------------------------------------+
| 26b608fc-d56b-4213-b56f-8f223cc7afca | HA network tenant 21306e7143ae4c70a8a8d04b7e801098 | c716f96c-c4b0-496a-b8da-df5d75c6592c 169.254.192.0/18 |
| c40fb5fb-ede5-401b-8fbc-479040f4cbf1 | HA network tenant feaf0caae2ab4c7085e19c2b516fe60b | 74674ddb-93ff-4134-bd3d-6fd6add7174a 169.254.192.0/18 |
| 727cc932-2b38-44a4-8298-f3d09449a0e8 | HA network tenant 4b3cd36777fe4cf2b3ef560384b57783 | c28097f1-ff7a-4f8a-bc14-a9ed327840e3 169.254.192.0/18 |
| f95b4c76-6d78-40bb-9bcd-7778fb75f688 | HA network tenant 3943b7f7c8d24dada236d6fb581eddca | a90be95e-2a19-483d-aebb-e1208a73398a 169.254.192.0/18 |
| c02632d5-f2b5-49dc-84c1-73434b014fae | HA network tenant fe4f692cd3cd439e81f9f71f25ecb226 | 6cd3c087-63f3-4638-b70c-5a148cec4ac4 169.254.192.0/18 |
[...]