Document name of report_type as "Scan Type" in UI

What does this MR do?

This MR adds a clarification that report type is also known as Scan Type in the UI. This connection is documented in the handbook glossary, but it needs to be more visible to users in the API.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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  • I have not included a changelog entry because this is a docs-only change.
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Availability and Testing

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

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