Refactoring some functionality out of the service package so it can be
reused by a different service package.
- auth middleware
- logging errors
No functional changes.
# 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/` or
`orbit/changes/`.
See [Changes
files](https://fleetdm.com/docs/contributing/committing-changes#changes-files)
for more information.
- [x] Added/updated tests
- [x] Manual QA for all new/changed functionality
