Debug log url

Created by: smithj382

Will close https://github.com/usgs/groundmotion-processing/issues/708

Getting the logging file name from the handler was a little tricky so the reviewer may want to check this way is not terrible:

for handler in root.handlers:
    if hasattr(handler, "baseFilename"):
        log_file = getattr(handler, 'baseFilename')

Autopep8 ran & pytest pass