add reaction heating

[aabills]

Description

Implements reaction heating in half cell models for the negative electrode

Fixes #4324

Type of change

Please add a line in the relevant section of CHANGELOG.md to document the change (include PR #) - note reverse order of PR #s. If necessary, also add to the list of breaking changes.

• [ ] New feature (non-breaking change which adds functionality)
• [ ] Optimization (back-end change that speeds up the code)
• [x] Bug fix (non-breaking change which fixes an issue)

Key checklist:

• [x] No style issues: $ pre-commit run (or $ nox -s pre-commit) (see CONTRIBUTING.md for how to set this up to run automatically when committing locally, in just two lines of code)
• [x] All tests pass: $ python run-tests.py --all (or $ nox -s tests)
• [x] The documentation builds: $ python run-tests.py --doctest (or $ nox -s doctests)

You can run integration tests, unit tests, and doctests together at once, using $ python run-tests.py --quick (or $ nox -s quick).

Further checks:

• [ ] Code is commented, particularly in hard-to-understand areas
• [ ] Tests added that prove fix is effective or that feature works

[aabills]

reaction heating implemented but I think heat source is still inaccurate for half-cell models.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 99.29%. Comparing base (19a7738) to head (7678703). Report is 3 commits behind head on develop.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #4557 +/- ## =========================================== - Coverage 99.42% 99.29% -0.14% =========================================== Files 300 300 Lines 22774 22776 +2 =========================================== - Hits 22643 22615 -28 - Misses 131 161 +30 ```

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[aabills]

I have found the second bug now. I think we should go ahead and merge this and discuss the second bug in a second issue, which I will open momentarily. The reason for a second PR is that the second bug could have ramifications outside of the files addressed in this pull request.

[aabills]

Not sure if we want to address this here or elsewhere (due to the second bug, this will fail for now), but I think we should start testing conservation of energy to catch stuff like this.