Fix mass conservative ridge coordinates which where interally not converted to radians.

[MFraters]

I found an issue with the mass conservative plugin where the ridge coordinates which where internally not converted to radians.

@mibillen

[codecov]

Codecov Report

Merging #352 (7c84044) into main (e73f0e0) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #352   +/-   ##
=======================================
  Coverage   98.84%   98.84%           
=======================================
  Files          76       76           
  Lines        4428     4434    +6     
=======================================
+ Hits         4377     4383    +6     
  Misses         51       51           

Impacted Files	Coverage Δ
...ucting_plate_models/temperature/mass_conserving.cc	97.20% <100.00%> (+0.12%)	⬆️

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[MFraters]

I now see why the tester didn't pick this up, there is test for the spherical case. I will add that to this pull request. The issue does not affect the Cartesian case, only the spherical case.

[github-actions]

Benchmark	Main	Feature	Difference (99.9% CI)
Slab interpolation simple none	1.216 ± 0.002 (s=368)	1.216 ± 0.004 (s=375)	-0.1% .. +0.1%
Slab interpolation curved simple none	1.568 ± 0.025 (s=263)	1.567 ± 0.022 (s=314)	-0.5% .. +0.4%
Spherical slab interpolation simple none	1.413 ± 0.005 (s=310)	1.414 ± 0.006 (s=329)	-0.0% .. +0.2%
Slab interpolation simple curved CMS	1.791 ± 0.062 (s=249)	1.788 ± 0.060 (s=257)	-1.2% .. +0.8%
Spherical slab interpolation simple CMS	3.016 ± 0.047 (s=153)	3.000 ± 0.045 (s=149)	-1.1% .. +0.1%
Spherical fault interpolation simple none	1.679 ± 0.071 (s=265)	1.684 ± 0.073 (s=273)	-0.9% .. +1.6%

[MFraters]

I have updated this after the merging of #354, and the results look good. So both this pull request is ready to be merged and think this is going to close issue #350 as well.