Resolves #45220 (one of several PRs) - [x] QA'd all new/changed functionality manually <!-- This is an auto-generated comment: release notes by coderabbit.ai --> ## Summary by CodeRabbit * **Tests** * Added a dedicated maintained-apps test helper and updated integration tests to use it, consolidating sync test setup and improving reliability of maintained-apps scenarios. * Updated several tests to use improved test utilities and helper variants for SQL test helpers and request fixtures. * **Chores** * Adjusted CI lint checks to exclude the new test helper location from specific env-var override validations. <!-- review_stack_entry_start --> [](https://app.coderabbit.ai/change-stack/fleetdm/fleet/pull/45494) <!-- review_stack_entry_end --> <!-- end of auto-generated comment: release notes by coderabbit.ai -->