Use Field Description for Product Recommendation example

[badmonster0]

https://github.com/cocoindex-io/cocoindex/blob/main/examples/product_recommendation/main.py#L93-L94

after #1087 is checked in.

We can move the docstring Fields on the individual field level.

Please also test it works as expected - following this https://cocoindex.io/docs/examples/product_recommendation

And update the documentation in the example as well.

[Pariharx7]

Hello
I would love to learn more about this project and contribute to the project.
Can you assign this issue to me?

[badmonster0]

assigned - Welcome to contribute and welcome to the community @Pariharx7 !

if you have any live questions, you can find us at - https://discord.com/invite/zpA9S2DR7s for discussion anytime!