Rasa community docs preview

[znat]

Proposed changes:

• preview of community docs

Status (please check what you already did):

• [ ] added some tests for the functionality
• [ ] updated the documentation
• [ ] updated the changelog (please check changelog for instructions)
• [ ] reformat files using black (please check Readme for instructions)

[github-actions[bot]]

🚀 A preview of the docs have been deployed at the following URL: https://11586--rasa-community-docs.netlify.app/docs/rasa

[xxxzc]

There is a misdescription in components.mdx#featurizers:

Sparse features only store the values

->

Dense features only ...