Configure SacRT for QA in test

[thekaveman]

SacRT would like to resume their evaluation of Benefits. They will use the test environment which is already mostly configured for the Older Adults + Login.gov flow.

Acceptance Criteria

• [x] Update SacRT Littlepay client secret (Key Vault)
• [x] Update SacRT Littlepay API URL, client ID, audience, card tokenize URL/env (Admin)
• [x] Ensure a testing group exists in Littlepay QA
• [x] Confirm Older Adult flow works as expected for eligible and ineligible users
• [x] Provide access to Benefits Test Data document for SacRT staff

[thekaveman]

@indexing provided access to the relevant documents.