Revert "Update smithy-rs to release-2025-07-21 (#1326)" (#1328)

This reverts commit 6ba5a63.

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Author: ysaito1001

config.json

@@ -1,5 +1,5 @@
 {
   "dependencies": {
-    "smithyRsVersion": "release-2025-07-21"
+    "smithyRsVersion": "release-2025-07-16"
   }
 }