pull request 155 (approved) did not update `arc.alkali_atom_functions.__arc_data_version__`

[CuriousCesium]

Hello,

I just noticed that there was a recent update to cs_NIST_level_data.ascii. To use the new values, the corresponding local data file in ~/.arc-data needs to be updated. I saw that arc.alkali_atom_functions.setup_data_folder is designed to update the local data files if there is a mismatch between version numbers stored in ~/.arc-data/version.txt and in the dunder variable __arc_data_version__. Because the pull request that updated cs_NIST_level_data.ascii did not update the dunder variable, my team members experienced a problem where users who had used arc module before got one value for a Cesium energy level and new users who freshly installed arc on their laptops got another value.

I think __arc_data_version__ should be incremented from the current value of 10 to 11 and I also wonder what can be enforced to prevent this kind of mistake in the future.

[nikolasibalic]

Fixed in 3.4.1. release.