relates to #17031
Adds functionality to create manual labels in fleet.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://fleetdm.com/docs/contributing/committing-changes#changes-files)
for more information.
- [x] Added/updated tests
- [x] M0anual QA for all new/changed functionality
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Co-authored-by: Martin Angers <martin.n.angers@gmail.com>