Deprecate old version of the docs website

[FabioPinheiro]

• Delete the old docs website infrastructure
  • Delete old staging docs website - https://staging-docs.atalaprism.io/
  • Delete old prod docs website - https://docs.atalaprism.io/
• Cleanup the old CI actions/jobs that build the website
• Clearly communicate to the community

[yshyn-iohk]

It looks like it's already done.
@FabioPinheiro could you confirm?

[FabioPinheiro]

Thanks for the clean up Yurii