How to upgrade PostgreSQL minor releases without a dump/restore?
If you are doing a minor version upgrade, nothing will or should touch your data directory.  If you are using binary packages, just run whatever upgrade procedure they provide (apt/yum upgrade, etc.).  If building from source, just do make install over the old files and then restart the server (pg_ctl restart or whatever you're using).

The documentation could perhaps be amended to say that you could even install the new binaries before restarting the server.