Adding Artelys Knitro solver API in PuLP

Describe the new feature
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Hi there,

I would like to propose adding a new solver API for [Knitro](https://www.artelys.com/solvers/knitro/), developed by [Artelys](https://www.artelys.com/). I believe it could be a valuable addition, considering it’s one of the most advanced nonlinear optimizersavailable.

I’ve already created a local version of the API, following the same structure and conventions as the existing solver interfaces in PuLP, which appears to be functioning quite well.
However, before preparing a pull request, I wanted to confirm whether there’s interest in integrating this solver into PuLP.

Additional info
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Please answer these questions before submitting your feature request.

#### Is your feature request related to an issue? Please include the issue number.
No

#### Does this feature exist in another product or project? Please provide a link.

https://www.artelys.com/solvers/knitro/

#### License
Knitro is a commercial solver, but a **one-month free trial license** is available at [Artelys Knitro trial program](https://www.artelys.com/solvers/knitro/programs/#trial).
This can be used to test and validate the new API.