Allow CreateAttachmentService to work with group

What does this MR do?

Allow CreateAttachmentService to accept group as scope.

I went with MVC by only modifying not its ancestor chains, because otherwise there will be 11 services requiring auditing. However I sil used the new keyword argument-based initialize.

Ref #207867 (closed)

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.