Migrate a Drupal 8 Site to Drupal 9 Doc Update

[mihailkrutikov]

Re: Migrate a Drupal 8 Site to Drupal 9

Priority: Low

Issue Description:

On the step 11 command terminus site:clone will not work for users who have no installed site clone plugin.

Suggested Resolution

Add a note to install the site clone plugin from https://github.com/pantheon-systems/terminus-site-clone-plugin