chore: sync AWS models and bump smithy-kotlin version (#686)

Author: ianbotsf

.changes/93d2e317-4264-460f-a9f5-a578db34178a.json

@@ -0,0 +1,5 @@
+{
+    "id": "93d2e317-4264-460f-a9f5-a578db34178a",
+    "type": "misc",
+    "description": "Upgrade smithy-kotlin to latest released version, 0.12.5"
+}

.changes/d1a26c04-4ffa-4658-9134-9b3a30a8907e.json

@@ -0,0 +1,5 @@
+{
+    "id": "d1a26c04-4ffa-4658-9134-9b3a30a8907e",
+    "type": "misc",
+    "description": "Sync AWS service models"
+}