[Bug report] Wrong KEYS file is updated in release script

### Version

main branch

### Describe what's wrong

The staging KEYS file is overwritten with the release KEYS files. While it is correct to use the KEY release version, this might come as a surprise to anyone making a release.

### Error message and/or stacktrace

No error occurs.

### How to reproduce

Run the release script.

### Additional context

_No response_

Start by locating the release script and tracing which KEYS file it writes during a release. Reproduce the behavior by running the script, then verify that the staging KEYS file remains unchanged while the release KEYS file is updated as intended.

Written by the indexing model from the issue text.