doc: add note about shasum generation failure

Author: marco-ippolito

doc/contributing/releases.md

@@ -944,6 +944,10 @@ a `NODEJS_RELEASE_HOST` environment variable:
 NODEJS_RELEASE_HOST=proxy.xyz ./tools/release.sh
 ```
 
+> \[!TIP]
+> In case <https://nodejs.org/dist/index.json>, <https://nodejs.org/dist/index.tab>
+> or `SHASUMS256.txt` have not been generated correctly, you can run `./tools/release.sh -s ~/.ssh/node_id_rsa`.
+
 `tools/release.sh` will perform the following actions when run:
 
 <details>