Manual steps required after old Bolt/BLT upgrade to 8.3.0/latest

[geerlingguy]

My system information:

• Operating system type: macOS
• Operating system version: 10.12.2
• BLT version: 8.6.5

When I followed the upgrade process outlined in the documentation, there were a few manual steps I still had to take to get the rest of BLT upgraded/operational. I wanted to document these steps here in case any other older projects want to upgrade and need the reference:

1. Delete the symlink in [root]/.git/hooks so blt local:setup would work (the hooks mkdir command was returning mkdir: hooks: Input/output error).
2. Delete all the items inside the [root]/tests directory besides the phpunit folder and the phpunit.xml file.
3. Delete the box directory entirely (since Drupal VM is installed as a dependency now), and then had to run blt vm to bring up a new instance (make sure devs run vagrant destroy -f before updating the codebase!). If you have customizations to config.yml for your project, make sure to re-add those to the new Drupal VM version.
4. Update the .travis.yml file using blt ci:travis:init.
5. Update the Drush aliases to use the Acquia Cloud URIs instead of the custom URIs (e.g. project.prod.acquia-sites.com instead of project.com). See: Drush commands error with "env: drush9: No such file or directory" #856
6. Update some of the modules (notably migrate and migrate_tools) to work with the newer version of Drupal core (composer started complaining because those modules don't work with Drupal 8.1.x, which the old composer somehow allowed through the old packagist).
7. Remove "drush/drush": "^9.0", from the require-dev section of composer.json and run composer update again to update the lock file.

There may have been one or two other issues... but I can't recall them at this time. It was quite an adventure in whack-a-mole!