Fixes to gstlal-calibration-devel RPM spec

This merge request addresses an issue relating to the gstlal-calibration-devel package where python-devel was specified instead of python3-devel. I've also organized the requirements for the package into separate Requires lines.

This looks like it also addressed some CI issues we've seen in the past where we weren't able to include gstlal-calibration in the containers published to containers.ligo.org or run relevant calibration tests in the CI.