Message from verification of bounds of p_ion should report the value of p_ion

[mchamberland]

Is your feature request related to a problem? Please describe.
In the TG-51 module, if your p_ion is out of range (1.00 - 1.05), you get an error that says so... but it does not tell you what the value of p_ion is, which makes it hard to troubleshoot what the problem is. For example, I had a typo in one of my chamber readings, but since I could not see the value of p_ion, I couldn't be immediately certain.

Describe the solution you'd like
The temperature and pressure checks report the value of those, so p_ion should do the same.

Describe alternatives you've considered
Calculating p_ion by hand with a calculator, like an animal.

Additional context
The calibration module is great. I report this nitpicky detail because I care.