Outdated information about Maven website deployment

### Bug description

- source code is in git - this repo
- jankis job is used for deploy

Site is referenced on:
https://maven.apache.org/developers/website/deploy-component-reference-documentation.html

### Maven site URL where bug exists

https://maven.apache.org/developers/website/deploy-maven-website.html

Start with the deployment documentation pages linked in the issue and locate their corresponding source in this repository. Compare the instructions with the stated Git source and Jenkins deployment process; done means the Maven website deployment information is current and consistent.

Written by the indexing model from the issue text.