Install contributor role if it doesn't already exist.

[stephen-cox]

Added update hook to install contributor role if it doesn't already exists

Closes #5

[Adnan-cds]

Hi Steve, Thanks for this change. I have test it and may have spotted two issues:

• I deleted the Contributor role from a fresh localgov install and enabled the localgov_workflows module. The Contributor role didn't come back.
• I reset the update hook number for localgov_workflows (i.e. drush php-eval Drupal::keyValue("system.schema")->set("localgov_workflows", 9000)') and followed by a drush --yes updatedb and this time the Contributor role showed up.

So this change clearly works on a site where localgov_workflows is already installed but perhaps not on sites which never installed localgov_workflows. This may be a nonissue given that every LocalGov site probably already have the localgov_workflows module installed, right?

After doing drush updatedb, I exported the config and noticed that the exported user.role.localgov_contributor.yml file is missing the UUID property. This may be an issue given that other role config files do have a UUID (and also the _core) property :(

[stephen-cox]

Thanks for taking a look @Adnan-cds

I should have fixed both issue.

• There's now a check to ensure that the contributor role exists when installing the workflow module - this could have happened if roles was enabled before the recent update but workflows wasn't.
• A UUID is added when creating the contributor configuration

[stephen-cox]

Thanks @Adnan-cds for the pointer the where we're doing this already. I realised it's better to use create the user role with

\Drupal::entityTypeManager()->getStorage('user_role')
  ->create($contributor_config)
  ->save();

as this adds the UUID without needing to do it manually.

[Adnan-cds]

Thanks Steve. Feel free to merge.