Remove landing page for Apify CLI

[patrikbraborec]

The landing page has several problem:

• The landing pages should motivate users to visit the particular documentation, but the conversion rate is quite low, and people go elsewhere instead.
• The landing pages add friction to the user flow.
• The landing pages have outdated information.

Let's remove the page, and move users directly to https://docs.apify.com/cli/docs.

Note: Please do not work on this issue yet as the discussion is still in progress.