For #26071 and #26089
Added `macos_setup.manual_agent_install` boolean option. No validation
(pushed to another story due to complications caused by bug #28497)
Tests are failing due to vulnerability issues that are not related to
this feature. All tests were passing earlier.
# Checklist for submitter
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
- [x] Added/updated automated tests
- [x] A detailed QA plan exists on the associated ticket (if it isn't
there, work with the product group's QA engineer to add it)
- [x] Manual QA for all new/changed functionality
Victor Lyuboslavsky
510a9bbc44