Added test for the Brieman magnetic braking model.

[RoryBarnes]

Proposed changes

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• Bugfix (non-breaking change that fixes an issue)
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[github-actions]

Test Results

19 667 tests   19 667 ✅  1m 39s ⏱️
     1 suites       0 💤
     1 files         0 ❌

Results for commit 62571a4.