gwcelery/tasks/inference.py: fix a bug in uploading bilby samples
This fixes a bug in uploading bilby samples caused by that bilby_pipe_to_ligo_skymap_samples can not find an input file by directory/*_result.hdf5.
This fixes a bug in uploading bilby samples caused by that bilby_pipe_to_ligo_skymap_samples can not find an input file by directory/*_result.hdf5.