Online PE broken failing to upload samples on playground

For all online PE triggers since Tuesday (e.g., here) the samples are not being uploaded due to a pesummary failure (e.g., this issue).

This is due to bilby_pipe_gracedb not resolving calibration files properly. I still need to figure out exactly why this is failing, but I'd like to make two changes to make the upload more resilient:

• two things are currently being done in _upload_tasks_bilby - uploading posterior samples, and launching a pesummary process to create webpages. These should be split so that a failure in one doesn't break the other. The posterior samples upload is much simpler and less error prone.
• the pesummary task is a little flaky because it assumes that optional arguments are provided in the Bilby config. These lines should have a fallback for None values.

cc @deep.chatterjee @soichiro

The failure finding the calibration files is due to a change in naming convention of the calibration files. Previously the files were named like /home/cal/public_html/archive/H1/uncertainty/v0/1407/601465/calibration_uncertainty_H1_1407601465.txt but they recently changed to /home/cal/public_html/archive/H1/uncertainty/v0/1407/601465/calibration_uncertainty_H1_1407601465_pydarm.txt.