Add secret fix for 3.1.7 (#161)

This PR extends opensearch_secrets.py to react to new secret-changed
behavior in Juju 3.1.7+, as described in
[LP#2037120](https://bugs.launchpad.net/juju/+bug/2037120).

.github/workflows/integration.yaml

@@ -76,7 +76,6 @@ jobs:
         with:
           provider: lxd
           juju-channel: ${{ inputs.juju-snap-channel }}
-          bootstrap-options: "--agent-version=3.1.6"
 
       - name: Download packed charm(s)
         uses: actions/download-artifact@v3
@@ -147,7 +146,6 @@ jobs:
         with:
           provider: lxd
           juju-channel: ${{ inputs.juju-snap-channel }}
-          bootstrap-options: "--agent-version=3.1.6"
 
       - name: Download packed charm(s)
         uses: actions/download-artifact@v3

lib/charms/opensearch/v0/opensearch_secrets.py

@@ -56,6 +56,9 @@ def __init__(self, charm, peer_relation: str):
 
     def _on_secret_changed(self, event: SecretChangedEvent):
         """Refresh secret and re-run corresponding actions if needed."""
+        secret = event.secret
+        secret.get_content(refresh=True)
+
         if not event.secret.label:
             logger.info("Secret %s has no label, ignoring it.", event.secret.id)
             return

tests/unit/lib/test_opensearch_secrets.py

@@ -27,6 +27,8 @@ class TestOpenSearchSecrets(TestOpenSearchInternalData):
     def setUp(self):
         self.harness = Harness(OpenSearchOperatorCharm)
         self.addCleanup(self.harness.cleanup)
+        # self.charm._on_leader_elected = Mock()
+        self.harness.set_leader(is_leader=True)
         self.harness.begin()
 
         self.charm = self.harness.charm