Authorizations: add limit query param

Authorizations do not have a limit query parameter that allows limiting results returned in the way that tasks or dashboards do.

### Acceptance Criteria
- Authorizations accept a limit to limit the number of results returned

Inspect the OpenAPI specification for the authorizations endpoint and compare its query parameters with those for tasks or dashboards. Add the documented limit parameter so authorization results can be bounded, then verify the specification accepts and describes that parameter consistently.

Written by the indexing model from the issue text.