Fix the file free space manager infinite loop bug

[derobins]

REF: https://github.com/HDFGroup/hdf5/blob/develop/testpar/t_filters_parallel.c#L10059-L10066

/*
 * TODO: Ideally, use persistent free space management. However,
 * this occasionally runs into an infinite loop in the library's
 * free space management code, so don't persist free space for now
 * until that is fixed.
 */
VRFY((H5Pset_file_space_strategy(fcpl_id, H5F_FSPACE_STRATEGY_PAGE, false, 1) >= 0),
     "H5Pset_file_space_strategy succeeded");

When the parallel compression tests (testpar/t_filters_parallel.c) are run with persistent free space management enabled, an infinite loop in the file free space managers will sometimes be encountered. Quick initial investigation seems to show this to be an issue where the same block of free space is getting repeatedly allocated and de-allocated, but more investigation is needed.