kubectl diff does not work with applysets

**What happened**:

```sh
❯ KUBECTL_APPLYSET=true kubectl diff --applyset=applyset/automata -f bazel-out/k8-fastbuild/bin/k8s/unwind/list.json --prune
error: unknown flag: --applyset
See 'kubectl diff -h' for help and example
```

**What you expected to happen**:

kubectl should show a diff of what changes would be made.

**How to reproduce it (as minimally and precisely as possible)**:

See above.

**Anything else we need to know?**:

ApplySets were introduced recently, I would have expected them to work with diff also.

https://kubernetes.io/blog/2023/05/09/introducing-kubectl-applyset-pruning/

**Environment**:
- Kubernetes client and server versions (use `kubectl version`): v.127.2
- Cloud provider or hardware configuration: N/A
- OS (e.g: `cat /etc/os-release`): N/A