Refactored to improve NilAway coverage (#42106)

<!-- Add the related story/sub-task/bug number, like Resolves #123, or
remove if NA -->
**Related issue:** Resolves #42092

Renamed the major anonymous functions so that NilAway analyzes them.

Disable whitespace differences when reviewing.

lint-incremental catches issues that were there already. Not a concern.
Main doesn't run lint-incremental, so we can merge with errors.

# Checklist for submitter

If some of the following don't apply, delete the relevant line.

- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.

## Testing

- [x] QA'd all new/changed functionality manually

## fleetd/orbit/Fleet Desktop

- [x] Verified compatibility with the latest released version of Fleet
(see [Must
rule](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/workflows/fleetd-development-and-release-strategy.md))
- [x] Verified that fleetd runs on macOS, Linux and Windows
- [x] Verified auto-update works from the released version of component
to the new version (see [tools/tuf/test](../tools/tuf/test/README.md))

changes/refactor-named-functions-nil-checks

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+* Refactored large anonymous functions into named functions to improve nil-safety static analysis coverage.

orbit/changes/refactor-named-functions-nil-checks

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+* Refactored large anonymous function into a named function to improve nil-safety static analysis coverage.