Fix `entropy` for quasi-1D compressible Euler

[jlchan]

Fixes https://github.com/trixi-framework/Trixi.jl/pull/1947/files#r1628569760

[github-actions[bot]]

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[jlchan]

There should be a test to catch this - there is not currently one, but I would propose making this a new issue instead of holding up https://github.com/trixi-framework/Trixi.jl/pull/1947/

Edit: ignore this comment, added a test in a098de3af688071fa41ec1581c4c9fd6086f56b4

[JoshuaLampert]

Formatting fails.

[jlchan]

Ah, I made some edits online so I didn't have a chance to run the formatter. One second.

[jlchan]

Hopefully that fixes things

[JoshuaLampert]

Doesn't look like the formatter is happy. Note that we use JuliaFormatter v1.0.45.

[codecov[bot]]

Codecov Report

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

Project coverage is 96.14%. Comparing base (2043cfe) to head (95b176b). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1974 +/- ## ========================================== + Coverage 96.13% 96.14% +0.01% ========================================== Files 460 460 Lines 36943 36942 -1 ========================================== + Hits 35512 35515 +3 + Misses 1431 1427 -4 ``` | [Flag](https://app.codecov.io/gh/trixi-framework/Trixi.jl/pull/1974/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=trixi-framework) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/trixi-framework/Trixi.jl/pull/1974/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=trixi-framework) | `96.14% <100.00%> (+0.01%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=trixi-framework#carryforward-flags-in-the-pull-request-comment) to find out more.

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[jlchan]

Thanks for the review!

[jlchan]

Merging; all tests passed