remove unnecessary 'setuptools' dependency (#385)

Contributes to rapidsai/build-planning#62.

It looks like this some of the `kvikio` conda package recipe has an unnecessary dependency on `setuptools`. I suspect that's left over from before the project was cut over to `scikit-build-core`.

This proposes removing it.

## Notes for Reviewers

How I confirmed there were no direct uses of `setuptools` in  this project:

```shell
git grep -i setuptools
```

Authors:
  - James Lamb (https://github.com/jameslamb)

Approvers:
  - Jake Awe (https://github.com/AyodeAwe)

URL: #385

CONTRIBUTING.md

@@ -39,7 +39,6 @@ The Python packages depends on the following packages:
 
 * Cython
 * Pip
-* Setuptools
 
 For testing:
 * pytest

conda/recipes/kvikio/meta.yaml

@@ -54,7 +54,6 @@ requirements:
     - {{ stdlib("c") }}
   host:
     - python
-    - setuptools
     - pip
     - cython >=3.0.0
     {% if cuda_major == "11" %}