Refactor FQA (combine sanity and mdx approach)

[oleksiisydorenko1]

Description

We need to refactor FAQ component, create an ability to configure path to mdx files on Sanity side

Technical approach

1. Go to FAQ component and update it to be able work with sanity
2. Create a schema on Sanity for FAQ data
3. Combine FAQ to work with Sanity and MDX