Add an extra.drush.services section to composer.json

Problem/Motivation

When using Drush 10.5.0 on a site with advancedqueue installed, I get the following message:

 [info] advancedqueue should have an extra.drush.services section in its composer.json. See http://docs.drush.org/en/10.x/commands/#specifying-the-services-file.

... the link there doesn't work - rather it is https://www.drush.org/latest/commands/#specifying-the-services-file

I get the sense that Drush 10 wants module developers to register any Drush services file(s) they define in composer.json, along with the version of Drush they're supposed to work with.

Proposed resolution

Add a composer.json. Add the following section:

  "extra": {
    "drush": {
      "services": {
        "drush.services.yml": "^9 || ^10"
      }
    }
  }

Remaining tasks

1. Write a patch
2. Review and feedback
3. RTBC and feedback
4. Commit
5. Release

User interface changes

None.

API changes

None.

Data model changes

None.