Drush 12 compatibility
-
3440974: Remove drush.services.yml and references to it
-
3440974: Add service definitions in purge.services.yml file At the same time, move files to correct location for Drush 12 discovery. Also add static create methods according to https://www.drush.org/12.x/dependency-injection/ to avoid having to use auto-wiring which is still an up-and-coming feature.
I did leave each create() method undocumented as their use should be quite self-evident and may also be temporary, especially if we opt to changing to auto-wiring already in this issue.
Closes #3440974