Rework coverage for NMODL ODE solver and pybind

[JCGoran]

Rework coverage so each invocation of nrnivmodl -coreneuron creates a coverage report if the ODE solver is used. Note that the coverage files may be littered across the source directory; this is due to the fact that nrnivmodl does too much "fixing" of paths of modfiles, so it's basically impossible to run it from the build directory itself (it does a cd beforehand).
Also note that the coverage tool is broken (see below comment), so we do not get coverage of all of the lines.

[github-actions]

✔️ e0e83ea -> artifacts URL

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 68.31%. Comparing base (9d29cc9) to head (ca5369c).
⚠️ Report is 16 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3544      +/-   ##
==========================================
+ Coverage   68.09%   68.31%   +0.21%     
==========================================
  Files         689      689              
  Lines      111038   111038              
==========================================
+ Hits        75615    75851     +236     
+ Misses      35423    35187     -236     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[azure-pipelines]

✔️ e0e83ea -> Azure artifacts URL

[JCGoran]

Okay, I am very confused how codecov is collecting and computing the coverage. For instance, I don't think this makes any sense:

This is taken from
https://app.codecov.io/gh/neuronsimulator/nrn/commit/e0e83ea869bea4aaebeb0ea77f5daa7103e6c6bc/blob/share/lib/python/neuron/nmodl/ode.py?dropdown=coverage#L132.

Note that one line (132) has no coverage, and then the line immediately following it (133), at the same indentation level, does have coverage? I have no idea what's going on here...

[github-actions]

✔️ c81be96 -> artifacts URL

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

✔️ 5cf9a74 -> artifacts URL

[azure-pipelines]

✔️ 47fa629 -> Azure artifacts URL

[mgeplf]

Note that one line (132) has no coverage, and then the line immediately following it (133), at the same indentation level, does have coverage?

I had a quick look; examining the .coverage file seems to show more proper coverage (at least 133 and 132 are covered):
coverage report --data-file=/home/mgevaert/src/nrn/build/test/nmodl/transpiler/unit/ode/.coverage -m gives

Name                                                    Stmts   Miss  Cover   Missing
-------------------------------------------------------------------------------------
....
lib/python/neuron/nmodl/ode.py                            244    118    52%   26, 34, 62-65, 69-72, 76-82, 86-91, 95-101, 105-110, 114-120, 137-140, 200-218, 245-252, 296-354, 383, 412-447, 526-535, 577-584

I wonder if it makes more sense to have coverage just make the .coverage file, and do a post process step to create the single .xml, that way other invocations wouldn't impact it?.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[azure-pipelines]

✔️ ca5369c -> Azure artifacts URL

[github-actions]

✔️ ca5369c -> artifacts URL