Harmonizing control of harvest modes for FATES and non-fates

> For the `fates_harvest_mode` update it was decided that we should segregate fates from `do_harvest` to avoid increasing complexity for this update since the `landuse_timeseries` option for fates harvest will be deprecated at a future date. As such I wanted to avoid allowing `do_harvest` with fates entirely.

_Originally posted by @glemieux in https://github.com/ESCOMP/CTSM/pull/2507#discussion_r1676188434_

Per discussion with @ekluzek, we should have a wider conversation about how we might want to harmonizing using harvest modes for CN and FATES to provide the user with the ability to set harvest with one option regardless of land model. We likely will want to address this once fates sunsets use of the `fates_harvest_mode='landuse_timeseries'` optin.