keyvalue deleted by ttl but not triggered

SUMMARY

When a keyvalue is deleted by the ttl, no core.st2.key_value_pair.delete is generated

STACKSTORM VERSION

st2 version: st2 3.7.0, on Python 3.6.8

OS, environment, install method

Post what OS you are running this on, along with any other relevant information/
OS: CentOS Linux 3.10.0-1160.76.1.el7.x86_64
Installation: one-line install

Steps to reproduce the problem

(cluster)-[root@auto ~]$ st2 key set test_ttl toto -l 30
+------------------+-----------------------------+
| Property         | Value                       |
+------------------+-----------------------------+
| name             | test_ttl                    |
| value            | toto                        |
| scope            | st2kv.system                |
| expire_timestamp | 2022-11-10T12:34:34.529983Z |
+------------------+-----------------------------+

(cluster)-[root@auto ~]$ st2 key list
+---------------------------+--------------------------------+--------+-----------+--------------+------+-------------------------------+
| name                      | value                          | secret | encrypted | scope        | user | expire_timestamp              |
+---------------------------+--------------------------------+--------+-----------+--------------+------+-------------------------------+
| test_ttl                  | toto                           | False  | False     | st2kv.system |      | Thu, 10 Nov 2022 13:34:34 CET |
+---------------------------+--------------------------------+--------+-----------+--------------+------+-------------------------------+

(cluster)-[root@auto ~]$ st2 key get test_ttl
Key Value Pair "test_ttl" is not found.

ERROR: Resource test_ttl not found.

 (cluster)-[root@auto ~]$st2 trigger-instance list
+--------------------------+--------------------------------+-------------------------------+-----------+
| id                       | trigger                        | occurrence_time               | status    |
+--------------------------+--------------------------------+-------------------------------+-----------+
| 636cefbc87c48a6504896824 | core.st2.key_value_pair.create | Thu, 10 Nov 2022 13:34:04 CET | processed |
+--------------------------+--------------------------------+-------------------------------+-----------+

Expected Results

Once the ttl expire the keyvalue is deleted by the system, it should create a trigger core.st2.key_value_pair.delete.

Actual Results

There is no trigger core.st2.key_value_pair.delete genereted but if you delete a key by hand, a trigger is generated

Start by tracing the TTL deletion path for key-value pairs and compare it with the manual st2 key delete path that emits core.st2.key_value_pair.delete. Reproduce the issue with st2 key set test_ttl toto -l 30, then verify that expiration produces the delete trigger while the existing create trigger behavior remains intact.