commented Fixing HDF5Matrix `.dtype` and `.shape` properties (#10749) * Fixing HDF5Matrix `.dtype` and `.shape` output Adding code to the initialization function of `HDF5Matrix` so that `.dtype` and `.shape` reflect the actual values returned by the normalizer * Update io_utils_test.py adding tests for normalizer functions that change dtype and shape * Update io_utils_test.py removing unnecessary whitespace to make pep8 happy