Follow-up from "Fix samples file"

The following discussion from !23 (merged) should be addressed:

• @jacob.golomb started a discussion: (+8 comments)

  Yeah I think the whole common_format executable is broken from this. When running with any environment using a version after the commit that changed that line, the job terminates and I get AttributeError: 'Namespace' object has no attribute 'sample_file'. Did you mean: 'samples_file'? in the .err file.

  I had not caught this because for the things we worked on while running these versions of GWPopulation_pipe I have not cared about the output of this executable, only the result file from the analysis stage. For reference, this bug was introduced well after the environment was made for my GWTC-3 populations paper runs.