Gracefully disable useRequest() cache when no request is active

[TylerHendrickson]

Description

This PR allows the recordsForUpload() function in packages/server/src/arpa_reporter/services/records.js to gracefully fall back to a cache-less implementation when no request is active. Generally, the useRequest() function helps recordsForUpload() implement request-scoped memoization (specifically, for avoiding multiple reads of the same file in the same request), but it causes workflows that are not triggered by a request to fail when recordsForUpload() is called.

With these changes, when recordsForUpload() is called outside the scope of a request, it falls back to a function-local, empty object (which will be GC'd after the function returns). This is admittedly a bit of a hack, but I think it's worth the tradeoffs. If it turns out that, even in a task-based environment, memoization is definitely necessary, we'll have to come up with an alternative mechanism for scoping a memoization cache to a per-task-message lifecycle.

Screenshots / Demo Video

Testing

Automated and Unit Tests

• Added Unit tests

Manual tests for Reviewer

• Added steps to test feature/functionality manually

Checklist

• Provided ticket and description
• Provided screenshots/demo
• Provided testing information
• Provided adequate test coverage for all new code
• Added PR reviewers

[codeclimate]

Code Climate has analyzed commit b1c8ecf and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 0.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 55.8% (0.0% change).

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