Closes https://github.com/fleetdm/fleet/issues/11837
Changes:
- Changed the OS icons used on tables/ and queries/ pages.
- updated `get-extended-osquery-schema` to change the `platform` value
of osquery table columns to be the normalized platform name (`chromeos`
» `ChromeOS`)
- updated `build-static-content` to support three `platforms` values
when adding platform compatibility notes to generated Markdown tables
(e.g., "**Only available on macOS, Linux, and Windows.**" )
- Added dropdown options and icons for ChromeOS on osquery schema table
pages, query details pages, and the query library.