Relax assertion in test_get_all_shards

when listing all shards, currently test expects to find only shards
that it has just created, but there could be other, pre-existing shards,
like default "None" one or shards created by other tests
running in parallel.

Instead, check that the created shards is a subset of all shards.

Change-Id: Ic35f9be232837922ae8ed857c7ea0bb58e064987
Signed-off-by: Pavlo Shchelokovskyy <shchelokovskyy@gmail.com>
diff --git a/ironic_tempest_plugin/tests/api/admin/test_shards.py b/ironic_tempest_plugin/tests/api/admin/test_shards.py
index 5a5e4ba..c2c83bb 100644
--- a/ironic_tempest_plugin/tests/api/admin/test_shards.py
+++ b/ironic_tempest_plugin/tests/api/admin/test_shards.py
@@ -137,7 +137,7 @@
     def setUp(self):
         super(TestGetAllShards, self).setUp()
         _, self.chassis = self.create_chassis()
-        self.shards = ["shard1", "shard2", "shard3"]
+        self.shards = {"shard1", "shard2", "shard3"}
         self.node_ids = []
         for shard in self.shards:
             _, node = self.create_node(self.chassis['uuid'], shard=shard)
@@ -146,6 +146,6 @@
     @decorators.idempotent_id('fc786196-63c7-4e0d-bd14-3e478d4d1e3e')
     def test_get_all_shards(self):
         _, fetched_shards = self.client.get_shards()
-        fetched_shards = [shard['name'] for shard in fetched_shards['shards']]
+        fetched_shards = {shard['name'] for shard in fetched_shards['shards']}
 
-        self.assertCountEqual(self.shards, fetched_shards)
+        self.assertTrue(self.shards.issubset(fetched_shards))