Bump openstacksdk to >1

This patch also vendors the openstack.cloud.subnet
module due to a problem with `disable_gateway_ip`
not being set for newly created subnets[1].

[1]: https://review.opendev.org/c/openstack/ansible-collections-openstack/+/940927

Change-Id: Ia021a1d7b82823c2e7498fdd66da3e2d5c6a8a79
(cherry picked from commit 8ccabb61cb8aa6a86c653cc47e43a648e8e07268)
diff --git a/.ansible-lint b/.ansible-lint
index 2776884..d6ddfd2 100644
--- a/.ansible-lint
+++ b/.ansible-lint
@@ -7,6 +7,7 @@
   - molecule
   - playbooks
   - plugins/filter
+  - plugins/modules/subnet.py
   - roles/defaults/vars/main.yml
   - roles/kube_prometheus_stack/files/jsonnet
   - roles/storpool_csi/files