More Snapshot metadata field verification >= 2.73

Fix Manage*SnapshotTest cases for API version >= 2.73
since a metadata field was added in that version.

Change-Id: I3595b4a5d51a739976243f1484179034993900ed
Closes-bug: #1993283
Signed-off-by: Goutham Pacha Ravi <gouthampravi@gmail.com>
diff --git a/manila_tempest_tests/tests/api/admin/test_snapshot_manage.py b/manila_tempest_tests/tests/api/admin/test_snapshot_manage.py
index 7e2f9f1..c628338 100644
--- a/manila_tempest_tests/tests/api/admin/test_snapshot_manage.py
+++ b/manila_tempest_tests/tests/api/admin/test_snapshot_manage.py
@@ -112,6 +112,8 @@
                          "provider_location"]
         if utils.is_microversion_ge(version, '2.17'):
             expected_keys.extend(["user_id", "project_id"])
+        if utils.is_microversion_ge(version, '2.73'):
+            expected_keys.extend(["metadata"])
 
         actual_keys = snapshot.keys()