nixos-rebuild: why is --update-input and --recreate-lock-file deprecated?

It's very convenient to specify either of those flags in `system.autoUpgrade` to regularly update my flake.lock file.

```
warning: '--recreate-lock-file' is deprecated and will be removed in a future version; use 'nix flake update' instead.
```

```
warning: '--update-input' is a deprecated alias for 'flake update' and will be removed in a future version.
```