ENG-8938: Add data source to retrieve user groups

[Yowgf]

Description of the change

Adds data source cyral_role. cyral_role can be used to retrieve roles that exist in the Cyral Control Plane. See Testing section below for an example of how to use the data source.

Type of change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklists

Development

• Lint rules pass locally
• The code changed/added as part of this pull request has been covered with tests
• All tests related to the changed code pass in development

Code review

• This pull request has a descriptive title and information useful to a reviewer. There may be a screenshot or screencast attached
• Jira issue referenced in commit message and/or PR title

Testing

The ACC tests added ensure that at least the data source can be deployed without generating errors. I didn't complete the full scenario for the ACC tests due to time constraints for this release, but added a TODO.

Manually tested with following config, and checked in local file that the contents are as expected.

data "cyral_role" "admin_roles" {
    name = "^.*Admin$"
}

resource "local_file" "admin_roles" {
  content = jsonencode(data.cyral_role.admin_roles.role_list)
  filename = "roles.json"
}

Also, if the name filter is an invalid regexp, we get a nice error message:

╷
│ Error: Unable to read resource
│ 
│   with data.cyral_role.admin_roles,
│   on test.tf line 1, in data "cyral_role" "admin_roles":
│    1: data "cyral_role" "admin_roles" {
│ 
│ provided name filter is invalid regexp: error parsing regexp: missing closing ]: `[.*Admin$`