[Docs][SyliusStack] add a "filters" section in the cookbook with links towards the Grid docs

[stlgaits]

The cookbook section of the documentation could benefit from a "filtering your data" section (or better name) which would showcase the basics of filtering and provide links to the grid bundle doc for full details like https://stack.sylius.com/grid/index/filters and https://stack.sylius.com/grid/index/custom_filter
The idea is to highlight the filtering / grid config section of the docs from the get-go so that users are encouraged to go and check it out from the start.