Suppress Parcels message about converting data

[angus-g]

For longer walltime advection, Parcels will helpfully give us a message like:

INFO:parcels.tools.loggers:Temporary output files are stored in tmp7sqhqa4z.h5.
INFO: You can use "parcels_convert_npydir_to_netcdf tmp7sqhqa4z.h5" to convert these to a NetCDF file during the run.
INFO:parcels.tools.loggers:You can use "parcels_convert_npydir_to_netcdf tmp7sqhqa4z.h5" to convert these to a NetCDF file during the run.

If possible, it would be nice to suppress this, since it doesn't apply in our case. I believe a condition for logging this is to have verbose output enabled, so another option might be to disable verbose output and log the advection progress ourselves.