update API doc required params - 4

- Account notifications
- Account reports
- Accounts
- Admins
- Accouncement external feeds

Test plan:
- rake doc:api
- Verify the above doc pages for parameter accuracy

Refs SIS-403

Change-Id: I13c95611a4f19683a38cdc743605ac1d202c9525
Reviewed-on: https://gerrit.instructure.com/38663
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Duane Johnson <duane@instructure.com>
Reviewed-by: Tyler Pickett <tpickett+gerrit@instructure.com>
Product-Review: Duane Johnson <duane@instructure.com>
QA-Review: Jeremy Putnam <jeremyp@instructure.com>