Fix share network subnet cleanup

The resource cleanup initiated within
'create_share_network_subnet' is currently
being ignored in the tests:

WARNING  [manila_tempest_tests.tests.api.base] Provided unsupported resource type for cleanup 'share-network-subnet'. Skipping.

The resource name is a typographical error.

Change-Id: If7359cb1ff8fab6fad194fc7efdb51a8ab3f8077
Signed-off-by: Goutham Pacha Ravi <gouthampravi@gmail.com>
diff --git a/manila_tempest_tests/tests/api/base.py b/manila_tempest_tests/tests/api/base.py
index 6372034..0674e96 100755
--- a/manila_tempest_tests/tests/api/base.py
+++ b/manila_tempest_tests/tests/api/base.py
@@ -757,7 +757,7 @@
         share_network_subnet = client.create_subnet(
             **kwargs)['share_network_subnet']
         resource = {
-            "type": "share-network-subnet",
+            "type": "share_network_subnet",
             "id": share_network_subnet["id"],
             "extra_params": {
                 "share_network_id": share_network_subnet["share_network_id"]