Fix Struct decoding for null (#4112)

* Fix Struct decoding for null

* CHANGELOG

* 6.5.2

packages/api-contract/package.json

@@ -10,7 +10,6 @@
   "license": "Apache-2.0",
   "maintainers": [],
   "name": "@polkadot/api-contract",
-  "private": false,
   "repository": {
     "directory": "packages/api-contract",
     "type": "git",
@@ -21,13 +20,13 @@
     "./detectPackage.cjs"
   ],
   "type": "module",
-  "version": "6.5.2-3",
+  "version": "6.5.2",
   "main": "index.js",
   "dependencies": {
     "@babel/runtime": "^7.15.4",
-    "@polkadot/api": "6.5.2-3",
-    "@polkadot/types": "6.5.2-3",
+    "@polkadot/api": "6.5.2",
+    "@polkadot/types": "6.5.2",
     "@polkadot/util": "^7.6.1",
     "rxjs": "^7.4.0"
   }
-}
+}