doc: Correct pull request prefix for scripts and tools

Author: MarcoFalke

CONTRIBUTING.md

@@ -149,7 +149,7 @@ the pull request affects. Valid areas as:
   - `net` or `p2p` for changes to the peer-to-peer network code
   - `refactor` for structural changes that do not change behavior
   - `rpc`, `rest` or `zmq` for changes to the RPC, REST or ZMQ APIs
-  - `script` for changes to the scripts and tools
+  - `contrib` or `cli` for changes to the scripts and tools
   - `test`, `qa` or `ci` for changes to the unit tests, QA tests or CI code
   - `util` or `lib` for changes to the utils or libraries
   - `wallet` for changes to the wallet code