Rename cleanup member fields

[denizergonul]

Description

In DefaultRequestHandlerModel:
m_pop_limit_pct is renamed as m_cleanup_min_occupancy_ratio.
m_pop_size_pct is renamed as m_cleanup_ratio.
m_pop_limit_size is renamed as m_cleanup_min_occupancy.

Let me know if you approve these name changes so I move on with the dependencies.

Obvious dependencies: appmodel daqsystemtest ehn1-daqconfigs

Not-very-obvious dependencies:

• lbrulibs used in python/lbrulibs/app_confgen.py which looks very old and outdated.
• dpdklibs used in python/dpdklibs/reader_confgen.py which looks very old and outdated.
• dfmodules used in test/config/hdf5write_test_hwmap.data.xml which looks current.
• dunedaq_conf_reader used in src/dunedaq_conf_reader/test/test-config.data.xml and src/dunedaq_conf_reader/test/test-config.data.json which look current.

So, dfmodules and dunedaq_conf_reader are also dependencies; lbrulibs and dpdklibsare not. Let me know if you disagree.

Addresses issue #10

Type of change

• Optimization (non-breaking change that improves code/performance)

Further checks

• Code is commented where needed, particularly in hard-to-understand areas

[jcfreeman2]

It looks like the code on this branch may need to be updated? The single-repo CI workflow that was triggered by the opening of this PR failed:

/__w/datahandlinglibs/datahandlinglibs/dev-a9/sourcecode/datahandlinglibs/include/datahandlinglibs/models/detail/DefaultRequestHandlerModel.hxx:15:46: error: 'const class dunedaq::appmodel::RequestHandler' has no member named 'get_cleanup_min_occupancy_ratio'
   15 |   m_cleanup_min_occupancy_ratio = reqh_conf->get_cleanup_min_occupancy_ratio();

[denizergonul]

It looks like the code on this branch may need to be updated? The single-repo CI workflow that was triggered by the opening of this PR failed:

/__w/datahandlinglibs/datahandlinglibs/dev-a9/sourcecode/datahandlinglibs/include/datahandlinglibs/models/detail/DefaultRequestHandlerModel.hxx:15:46: error: 'const class dunedaq::appmodel::RequestHandler' has no member named 'get_cleanup_min_occupancy_ratio'
   15 |   m_cleanup_min_occupancy_ratio = reqh_conf->get_cleanup_min_occupancy_ratio();

Hi,
The PR is incomplete, actually. (Maybe now that I converted it into Draft it makes more sense.)
I wanted to check first if the new names that I'm suggesting are okay.