chore(codegen): bump '@smithy/*' versions

Author: trivikr

scripts/generate-clients/config.js

@@ -1,7 +1,7 @@
 // Update this commit when taking up new changes from smithy-typescript.
 module.exports = {
   // Use full commit hash as we explicitly fetch it.
-  SMITHY_TS_COMMIT: "cc2105a5dd5dfe01ace384034e863770080e6b08",
+  SMITHY_TS_COMMIT: "b20705ddfc05e7eba3fc3669888f576622474e9c",
 };
 
 if (module.exports.SMITHY_TS_COMMIT.length < 40) {