Improve an unclear exception message when parameter names are not valid identifiers

[michaelstoops]

There was an unclear exception message in parameter_base.py.

I made it more clear.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.94%. Comparing base (df22e8a) to head (b6f5697).
⚠️ Report is 22 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7862      +/-   ##
==========================================
+ Coverage   59.87%   59.94%   +0.07%     
==========================================
  Files         352      352              
  Lines       31872    31932      +60     
==========================================
+ Hits        19083    19142      +59     
- Misses      12789    12790       +1     

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[jenshnielsen]

Thanks @michaelstoops

In the future I would recommend pr titles that descript the change rather than the issue. E.g. something like Improve error message when parameter name is not a valid identifier

[michaelstoops]

Fair point, @jenshnielsen. I've adjusted this PR.

I was going to add some guidance to CONTRIBUTING.rst. I see that the existing text suggests the use of a template.

The template will help you write nice pull requests <3 !

What template does it mean?

Michael